Project Carbon Next Gen 10 Speed Valve Body Kit - Finally Installed!

[jfoj]

I can see a lot of the V8 models not getting transmission services due to the PITA exhaust "Y" pipe. This is main reason I am changing the trans pan to an aftermarket one with a drain.

A lot of the YouTube videos indicated that many of these trans pans have drains, they are not drains, they are bottom fill tubes with a standpipe. There German models used these bottom fill tubes with standpipes, BUT, you could usually use a 6mm or 7mm hex driver to unscrew the standpipe and drain most of the fluid from the pan. Not sure what models still have the bottom fill standpipe, but again, it is not a drain. My 2024 has a solid pan without the bottom fill/standpipe option.

The bottom fill/standpipe is actually genius and works very well. It makes checking and filling the transmission very easy and accurate. The problem is the stupid overly complex and expensive fill tools the manufacturers offer. They are not needed, a $7 fluid pump from the parts store and a pan adapter is all that is needed. I actually had a blow gun extension that had the correct metric thread and was about 3/8" diameter I used for many German bottom fill automatics. It works great and it was not like the overly complicated IV type pump the manufacturer said was required.

 

[operator5362flink]

I ordered the Next Gen kit 2 weeks ago. Still waiting for it to ship. I think they may be getting slammed after all the recent attention. I noticed on their site today that the shift valves are now always included in the kit rather than being an add-on, but the combined price dropped $49 to $1399.

I already have ready a new filter, ATF, Sonnax check balls, and various “one-time-use” seals and bolts as called for in GM Service Info in Alldata.

I plan to add a drain plug to the stock pan while I have it off. Hopefully that won’t leak!

I also bought a second external bypass unit (diesel only) and updated it with the Superior Transmission Parts STL020 kit to eliminate the thermostat. This changes it from a thermal bypass of the transmission cooler when the fluid is cold to a pressure bypass in case the cooler gets restricted or blocked. I will install this as an experiment to see what difference it makes, prior to installing the Next Gen kit.

Fortunately, having the diesel I won’t have to mess with the exhaust!

 

[jfoj]

@operator5362flink

Call NextGen about your order, mine was taking like 2 weeks, I called and it shipped out right after I called. Not sure how they operate but it seemed that my order was shipped from somewhere in the North East US.

I think their shipping folks needs to get better organized.

I spoke with Nate a while ago and I think they were deciding that it was better for the end user in the long run to get a valve body kit with the valves to eliminate other problems, why play "Whack A Mole". While it is more expensive, just do the job once and get the majority of the problems out of the way.

I also think there may be some smaller running changes to their kits that may eliminate a few parts as well.

Be careful with the documentation, I was sent 10L1000 details, clearly a LOT of differences in these transmissions over time. Gen 1 was 2019-2021 as I recall, then there were valve body changes. Additionally there are electronically shifted versions that do not have the manual valve and have a different electrical connector, actually a bit simpler flat connector with a release bail. Then there are units with a Auto Stop/Start electrical auxiliary fluid pump. Then at least with my transmission all the valve body bolts are E Torx or external Torx, 2 different sizes, smaller for the filter and a bit larger for the valve body to transmission bolts.

I even purchased a manual and between this info, what Next Gen sent which was for the 10L1000 which is pretty much the same, but valve body removal is different and online info, I think I have 4 different sets of info that does not all agree.

The units with the Auto Stop/Start auxiliary electric fluid pump has hard metal fluid line and O-ring that connect to the valve body that needs to be disconnected to remove the valve body.

I think the internal parts/valves/solenoids of the valve body are more similar overall. But a lot of variations on the installation and bolts.

 

[89Suburban]

@NickTransmissions not sure if you seen this thread or interested any of the info in it.

 

[jfoj]

Not sure why I have all these left over parts???

 

[jfoj]

Below is a YouTube video that shows where the 3 bolts with sealer go that are 3 of the 7/9 bolts that hold the valve body to the transmission case. I mention 7/9 bolts, there are bolts that hold the valve body to the transmission case and the other 2 are the filter bolts.

I sprayed brake cleaner in the 3 bolt holes and let them dry out to get any residual ATF that may have been in these holes washed out. Not sure if this just blue Loctite or something special, but there factory bolts in these 3 holes had sealer, so best to put things back the way they were meant to be.

A few words of caution, the valve body is HEAVY, so be prepared. If the vehicle has Auto Stop/Start with the electrical auxiliary fluid pump, there is a hard pipe that attaches to the corner of the valve body and there is a O-ring between the flange and the valve body that needs to be removed before the valve body comes out, best to remove this hard pipe first. It is near the electrical connector.

Picture of hard pipe disconnected and moved to the side, bolt threaded partially back in the hole, this is not a VB mounting bolt. Hard pipe can either be removed or swung around out of the way, I swung the hard pipe around and rested the flange on the cross member or exhaust so it would not fall out. There is just an O-ring sealing the end that is installed in the Auxiliary pump.

Also note the brown multi connector flat electrical connector with the gray release bail. Some of the cable shifted transmission have a different round connector with fewer wires. The gray connector release needs to be pulled prior to removing the valve body. Easy to release and it will force the connector out of the socket about 1/2 way.

Where the other 2 bolts with sealer go, this mounts a sensor that has a wire connected, best to remove these 2 bolts and the sensor before you plan on dropping the valve body. All these small connectors have a small red locking tab that needs to be pushed down so you can push the connector release tab. It is a bit hard to see but the release tab is sandwiched between 2 small ridges on the connector. You will probably need a small 90 degree pick tool to easily depress the locking tab. Once the sensor is loose it will probably be easier to see how to push the red locking tab to the unlocked position to then find and press the connector release tab. There are about 10 of the same type of connectors on the valve body that you will need to unlatch. Remember to plug everything back in and lock all the red tabs back in place before you put everything back together.

I think this is a Park sensor that has the 2 other bolts with the sealer installed. This is on the drivers side near the rear of the transmission.

The transmission temperature sensor is on top of the valve body in the middle. Before you flip the valve body over, best to release the cable as above, depress the temp sensor locking tab and turn 90 degrees to release and remove the temp sensor. This will keep you from breaking the sensor with the valve body weight.

Suggest you quadruple check the torque on all bolts. This way you will not hopefully miss any of the bolts. On the electrically shifted transmissions there are a few valve body half bolts that are under the wiring harness or the small supplemental valve body that need to be installed and torqued before the small supplemental valve body and wiring harness is mounted and bolts for the wiring harness is installed.

I will also try to comment on the level if difficulty and some things to watch out for. I have done a fair amount of transmission work and this was not overly difficult, BUT if you have the large valve body separator plate off (held on by 2 T30 Torx screws which is a good thing) and turn the large valve body over, you may be in for some surprises because in addition to the 5 check balls there are 3 or 4 small pistons that go in the the large portion of the valve body.

I also did not fully disassemble the valve body because it only had 8k miles and no major failure, so there was not any debris in the valve body. So I changed each valve one at a time, so as not have bunch of random valves and springs to get confused. There are 3 different shift valves in the kit, 2 each of 3 styles, you need to carefully match up each shift valve when you remove them.

Will try to add more when I get a chance.

PPE aluminum transmission pan with drain. This pan holds about 2 1/2 quarts over stock which is good because I think no more than 3 quarts came out when I dropped just the trans pan. More fluid leaked out once I was able to get the valve body loose which is pretty typical. So just doing fluid services on this transmission will not rotate much fluid out. With the valve body mounted cooler thermostat, not sure you could flush/fluid exchange via the cooler unless there is a check valve as part of the thermostat. Having to drop the exhaust on the V8 trucks to change the fluid and filter will limit how many people actually get the transmission serviced! I will probably drain and fill the transmission ever other oil change give the small amount that will actually come out of the trans pan.

 

[jerry455]

That pan looks great. When I did the fluid and filter after Christmas, I never got out the amount that the service manual said, 8.1 quarts. I only got around 6-6.5 quarts. I try to replace what had come out.

 

[jfoj]

I might be wrong about how much came out when I dropped the pan, I am using a large concrete mixing pan as a catch pan and I think I maybe had less than 1 inch of fluid in the bottom of the pan. I clearly had more fluid come out once I loosened up the valve body.

My PPE pan is for the V8 Yukons/Tahoe/Esclade. If you have a Diesel, you may not need the pan with the shallow part that is above the exhaust cross over pipe.

Luckily PPE modified their casting for the gas trucks with the exhaust cross over under the trans pan.

 

[blanchard7684]

@jfoj did you drop the exhaust cross over?

 

[jfoj]

@blanchard7684

I did not need to disconnect the exhaust after the "Y" pipe, so I did not need to actually remove any exhaust parts from under the vehicle. I did need to disconnect the 3 flange nuts on each side of the exhaust manifolds and just drop the "Y" pipe down a few inches. There is a flexible exhaust coupler so there is some flex to allow the "Y" pipe to droop a bit.

Had to pull the driver side upstream O2 sensor as well.

Glad I did this when the vehicle was still a youngster, would hate to have rusted exhaust studs and nuts. Anyone that has any plans of keeping their vehicle and dropping the trans pan in the future should get some Anti-Seize compound and at least remove 1 nut at a time and load the stud up with Anti-Seize so any future work will hopefully be easier. I hope GM used something other than standard steel studs so they will not rust to a 1/8" inch and break in the future.

A real PITA just to drop the trans pan.

 

[blanchard7684]

Fantastic info thanks

 

[operator5362flink]

@jfoj Any changes you notice in the operation of the transmission after the valve body updates?

 

[jfoj]

Quick update. Everything is back together, drove about 6 miles last night and put the truck up on ramps last night to do another fluid check when truck cooled down. Topped fluid off this morning again and ran out after 12 quarts. New pan holds 2 1/2 quarts more than stock pan. I think I am within 1/2-1 quart of proper fill. More fluid on the way.

The thing anyone doing this job needs to be prepared for the Check Engine Light, Major Transmission Trouble Codes and Permanent Transmission Trouble Codes!

This is to be considered "Normal", but not mentioned anywhere. This is due to the transmission fluid draining out, the valve body being empty, the pump losing its prime, a new filter that has not had fluid circulated thru it. I filled the transmission until the fluid started to drain out of the fill plug, then started the engine. I initially had a message on the dash something along the lines of "Conditions Not Met To Shift" or something like this.

Put trans in Reverse and Drive then left engine running and topped fluid up until it started to drain out the fill plug. Put fill plug in, then backed truck off ramps. Grabbed OBDII tool and had 5 different Transmission related DTC's. Cleared the codes, Check Engine Light went out but still had 3 Permanent codes. Took truck for a quick 10 mile test drive on local roads. Transmission seemed to be shifting fine.

Put truck back up on ramps upon return so I could check the fluid level again this morning. Took all the fluid I could get out of my pump. Probably within 1 quart of proper level at this point. Drove another 25 miles this morning to run an errand. Took local roads and about 8 miles on the highway. 100F ambient temp today!!!, trans temp never went above 145F. Seems to be shifting even better now that fluid level is almost correct and the shift valves are starting to get worn in. Stopped to drop off the O2 sensor socket kit back at the auto parts store. When I arrived back at the house, checked for the Permanent transmission codes and they had all cleared. Usually for Permanent code to clear there needs to be X miles and X start cycles before they automatically clear. So I hit the magic target and the Check Engine Light stayed off and never came back on during any of the test drives.

What I can say is I like the change in the shift quality. Before the shifts were a bit too long and drawn out, not as precise. I recall that either the 3-4 shift or 4-5 shift was a bit long and had a slight "flare" IMHO before. I think there is a slight fluid pressure increase and maybe a few holes in the separator plate may have been increased in size slightly.

This was not an "easy" job more due to the exhaust needing to be dropped. The valve body is like a 3 layer sandwich and if someone flipped the main lower part over, without more documentation or experience you could be in trouble due to 2-3 small springs that are slightly different in size that could come out. If you take your time and think before you make any moves you should be in good shape. As mentioned, I did not fully disassemble and remove all valves and parts to a bare valve body, I pretty much changed one valve at a time which made for less of a chance of something being mixed up. Given the transmission only had 8500 miles and no major failure, cleaning the valve body fully was not really necessary.

Will try to list tools with pictures and make some suggestions about what to watch out for if you plan on doing this type of job. If you have big hands and arms, it may be tricky to get around the exhaust to start nuts or get sockets to line up on the exhaust nuts. If your truck is more than 1-2 years old, not sure how tricky it may be to get the "Y" pipe nuts to bust loose without breaking a manifold stud. The catalytic converters are mounted up high close to the exhaust manifolds, so this is what makes access to the "Y" pipe nuts a bit trickier.

Bottom line, the valve body and PPE trans pan are well worth it from my initial observation. Being able to at least drain the trans fluid every 2nd oil change will be helpful and will hopefully prolong the transmission lifespan. The improved, quicker and more precise shifts feel better IMHO. I do not like a transmission that tends to shift too smooth or have too much shift overlap. To me this behavior just equals more heat and more wear. The NextGen valve body separator plates are 2-3 times thicker than OE and they DO NOT have a thin paper gasket that can blow out and cause internal valve body leakage.

If anyone has specific questions or is thinking on DIYing this, PM me.

The valve body job is not for a novice, especially since the exhaust is an issue on the V8 gasoline engines, the 3.0 Duramax should not require exhaust removal and I think the 2500 series trucks may have room to remove the transmission pan without exhaust clearance issues.

HIGHLY recommend the PPE aluminum pan with the drain. While you could put a drain in the OE pan, I am pretty sure the OE pan is thin aluminum and a drain plug could be problematic. The PPE pan adds 2 1/2 quarts more fluid and seems far more structurally sound than the OE pan.

Shut off the A/C before you do this job, the evap drains right on top of the transmission and will be getting you wet. I took longer to do this job because between my family commitments over the last 6-8 weeks, tons of rain I finally shipped the family off for 3 weeks. The problem is it has been triple digit temps and high humidity the last 3 days, so I would only work for a few hours at a time and then try to cool off and dry off. Try to hold tools with trans fluid on your hands and sweating like a cave man! Went through a roll of paper towels on this job!

 

[operator5362flink]

@jfoj Thank you for this very helpful thread! Congratulations on persevering through weather and family commitments.

I will be following behind, maybe in the next week or so. Do the procedures for disassembling the valve body in Service Update N242483540 look good to you, especially the approach for separating the halves so nothing falls out?

I’m going to try adding a drain to the stock pan, but can always switch to the PPE pan later if needed. I will still drop the pan for fluid changes — the drain is to make that less messy.

 

[jfoj]

At least my 2024 Yukon 10L90 had 10 check balls, there appear to be some variations on the valve bodies. There were 2 check balls on the underside of the area where the small Auxiliary valve body was located. None of the documentation I had mentioned these check balls. I picked up the valve body and found these 2 check balls nestled in the packing paper that the NextGen kit came in so the check balls did not really move. I figured out where these went by inspecting this portion of the valve body, but these check ball cavities were much deeper than the others. I do not recall taking a picture of this area, but there are 2 check balls under the area where the Auxiliary valve body is located. I think you need to take off the mid size separator plate to see these and DO NOT flip the valve body over until you note where they are located.

 

[jfoj]

Going to post some suggestions, tips and so forth for the valve body rework. I will probably edit and add to this as time permits, but wanted to get this started.

Transmission Fluid

Suggest running the AC Delco ULV fluid that is speced for this transmission. Rock Auto seems to have the best pricing that I could find even with shipping. Under $6 per quart plus shipping. I have not had much luck finding is locally and even if I could order it locally, it was $11-$12 per quart.

You should be able to do the job with a case of 12 quarts unless you install a larger capacity trans pan. The PPE stepped pan that is designed to clear the exhaust cross over on the V8 vehicles holds an extra 2 1/2 quarts. I think with this 2 1/2 quart extra capacity you will need close to 13 quarts, I should have a better idea on this when my extra fluid arrives today and I perform the final top off of the fluid level.

You WILL need a fluid pump of some sort to fill the transmission. You could use one of the manual $7 parts store fluid pumps, but for between 9-13 quarts this could take some time and elbow grease. Some folks get a new 2 gallon pump garden sprayer and modify the hose to make it longer and work out a valve of some sort. Some just purchase a fluid pump that holds 2-3 gallons from Amazon or some of the other auto tool providers. If you end up putting a drain in your OE pan or going with an aftermarket pan and plan on regular fluid drain and fills, I would invest in a pump with a 2-3 gallon capacity.

SHAKE the fluid containers before you pour into the pump tank or pump into the transmission. If you pour the fluid into a pump tank suggest you shake the pump tank when about the transmission is about 1/2 filled, or around ever 1 gallon. The additives can easily settle out of suspension and this is a WISE process to get in the habit of. Do the same with your engine oil as well.

Checking and setting the fluid level. The final fluid level needs to be set WITH THE ENGINE RUNNING. And when the fluid it topped of with the ENGINE RUNNING, you need to install the fill plug BEFORE turning the engine off. There are so many BAD ideas on YouTube videos that it drives me crazy. I do not think the non heavy duty trucks have the bottom fill port on the transmission pan. I have seen a number of the 10L1000 that appear to have the bottom fill port with the standpipe, but I have not seen these on the 2023+ 1/2 ton trucks.

With the initial fill, pump fluid into the trans until it just starts to drain out. Start the engine, you WILL have a Check Engine Light and a bunch of transmission related codes. Do not worry, if you did the job right, you can clear the non Permanent codes and the Permanent codes should clear after a number of drive cycles. Once you start the engine foot on the brake, shift to Reverse then Drive, repeat, then put back in Park. While the engine is still running slide back under the vehicle and start pumping more fluid into the transmission until it starts to drain out. Be CAREFUL the catalytic converters and exhaust will be warming up quickly. Once fluid is starting to drain again, insert the fill plug and then shut vehicle off. Make sure to tighten fill plug and clean up any trans fluid. Then it is time to get an OBDII tool or App. Trans codes will show up with almost and lower engine OBDII tool or App. Read the codes, save or screen shot the codes just for reference. Clear codes, the Check Engine Light should clear, but you will probably have 3 Permanent codes still. Test drive the vehicle, driving it easy, but drive it to get it up into 10th gear for a bit to purge all air out of clutch packs, servos and valves. Bring vehicle back, put back on ramps and allow to cool overnight to recheck fluid level on the next restart. Top fluid level up until it just starts to drain from fill plug.

As for the stupid 176F fluid temperature check, I would HIGHLY NOT RECOMMEND this process it is stupid and very dangerous. 176F fluid can severely burn you along with the hot exhaust and depending on the exhaust pipe temperature, you could have the a transmission fluid flash fire under the vehicle if fluid hit the hot exhaust. Additionally since the fluid temp sensor in mounted in the top of the valve body and effectively measures the valve body core temperature if you are brake torqueing/power braking the transmission to allow the torque converter to heat the fluid, if you are not patient, you could risk overheating the torque converter because it will take some time for the fluid to circulate in the valve body until the trans temperature shows an increase. Additionally I am sure the TCM/ECM has a slower refresh rate on the trans temperature so it does not show rapid fluctuations on the temperature display.

My testing and recommendation it to verify the fluid level at around 100F fluid temperature. Fill with engine running until fluid starts to drain out of the fill plug. If your vehicle still has the transmission fluid thermostat installed, either in the valve body for gasoline engine vehicles, or the external cooler line mounted thermostat on the Diesel engine equipped vehicles this is my suggestion. Unclear if the transmission internal temperature sensor really follows the transmission thermostat temperature closely. I would drive the vehicle for 1-2 weeks and get the allow the transmission temperature to get as high at it typically would, then just recheck the transmission fluid level after 1-2 weeks of driving. A pan drop and drain will not likely allow the cooling loop to drain, but valve body removal will likely allow some of the fluid in the cooling loop to drain. I do not know if the cooling loop has a small amount of fluid that will circulate to purge air or if the thermostat actually has to open for fluid flow??

You will also want to drive the vehicle for a few hundred miles for the new valves to break in and the O-rings to get settled. During this time the TCM should also be adapting as well. I will say so far I am very happy with the differences in the shift quality. I prefer slightly firmer and more precise shifts rather than sluggish overlapping shifts that seem to cause cause excessive transmission clutch wear over time. I have found that the shifts are quick and crisp, but not overly firm. I used to feel a flare or delayed 2-3 or 3-4 shift that too me felt like a struggle or just excessive shift overlap. This appears to be gone now. I have not really put my foot into it yet but I had to merge onto a busy highway with a short merge ramp and put my foot into it slightly and the shifts did feel firmer and what I would like to have when winding the RPM out a bit. More to follow once I perform the final fluid check and get some more miles on the vehicle.

I initial thoughts are that NextGen did a good job with a slight pressure adjustment, better valve sealing and reduction of other possible leak points and I have no idea if they enlarged any of the separator plate fluid passage holes. But clearly there were changes and overall I am pleased with the upgrade and outcome. I have not had to change to play with the transmission Tow or Sport modes, but I expect them to be improved with the valve body, valve and spring updates. If you tow on a regular basis with your vehicle, I would HIGHLY recommend this upgrade along with a PPE trans pan to fit your application.

My plan it to perform a transmission fluid drain every 2nd or 3rd oil change now that there is a drainplug in the transmission pan. For me, this will probably be every 7-11k miles. Since I think I will only get about 5-6 quarts of fluid out even with my larger trans pan, I would rather drain the fluid more often than not. As for filter changes, with the V8 requiring dropping down the exhaust from the manifolds, not sure how often this may happen if at all. Probably will monitor the fluid and magnetic drain plug for glitter and material to make this an audible call. The exhaust cross over on these models makes it just a PITA to perform a transmission pan drop and filter filter change. I expect a lot of these vehicles to not have transmission services. Not even sure if you can perform a fluid exchange with the transmission fluid thermostats on these vehicles.

 

[jfoj]

A few comments and pictures on the valve body.

Valve body is held in by 9 screws, 2 are the E8 Torx screws that hold the filter on, these should come out first. Then there are 9 - 8 mm hex bolts. But before you make a move on the valve body bolts, you need to disconnect the hard pipe from the Auxiliary Electrical Fluid pump that is part of the Auto Stop/Start system. There is an O-ring between the hard pipe flange and the valve body that is about 3/8" diameter. There is 1 bolt that does not hold the valve body to the transmission case. It is a longer bolt, pretty much a valve body assembly bolt. The hard pipe can be removed or swiveled out of the way.

Then unlatch the electrical connector bail, it will partially eject the connector, but there was not enough slack to fully unplug the electrical connector. The bail is the gray ribbed part on the brown electrical connector. Pull is downward and it should unlock and start to back the brown connector out of the socket. Once you start to lower the valve body the connector should easily separate if the bail is released.

Then the next thing to do is disconnect the wire on the small sensor near the side of the Auxiliary valve body. The red locking tab will need to be slid so the actual locking tab can be depressed to release the connector. It is a little tricky to figure out. I used a small 90 degree pick tool to depress the release. Do not force anything. If for some reason you cannot figure it out, you can leave the sensor wire connected and sort it out when you remove the valve body.

Once you have the 2 sensor bolts removed, there are only 5 more valve body bolts.

All the valve body to transmission bolts have an arrow pointing at the bolt cast into the valve body. They may be tricky to see while the valve body is still in the transmission. The more light, the better.

The valve body is HEAVY, so I would find the 5 remaining screws and back them out a few turns and you will know when the valve body is getting loose because a lot more fluid will drain. I loosened the valve body bolts about 4 turns and let the fluid drain for quite a while before I pulled the valve body. Have some cardboard or a box with some paper in it to lower the valve body into once you start to remove it from the transmission.

Suggest you put the valve body face down, the side you removed all the bolt from, but if have to flip it over, it is best to have paper or something to keep all the weight of the valve body off the temperature sensor that is located in the top middle section of the valve body.

IMHO you do not need to keep close tabs on the valve body bolt length or location as there are only a few different length bolts and it is easy to figure this out. You could sort this if you wanted to once the valve body is on the bench.

A few suggestions about bolt location when disassembling the valve body. I would leave the bolts in their respective holes on the smaller Aux valve body when you remove it. This way you save time and do not need to worry about what bolt goes where and what length.

I would grab a piece of cardboard to make a bolt holder for the bolts for the main part of the valve body. Again, saves times, cuts down on confusion. Draw some reference points, mark empty bolt holes etc. This was my masterpiece!

Checkballs!!

Overall not too difficult to keep track of, but there are 2 check balls in the area under the small Aux valve body that were not documented well anywhere. So be on the look out for them, these checkball cavities are deeper than most of the others, so be aware of this. I do not have a picture of this unfortunately.

When changing things like the Lube Regulator Valve spring and the Feed Limit Valves be careful as the springs will pop out when you remove the retainer. Make sure you are prepared to capture the spring as it tries to escape! When reinstalling the springs and trying to get the retainers back in, I used different sized 1/4" deep sockets to push the spring back in and then work the retainer back in place to secure the springs.

Once you get the smaller Aux valve body off and are ready to split the valve body into 2 pieces, make sure the larger top have of the valve body with the shift solenoids has the separator plate face up. There will be 2 T30 Torx screws that will need to be removed to take the large separator plate off. Once this large separator has been removed, DO NOT turn over this portion of the valve body as there are a number of small pistons and springs in the valve body half that will fall out. You will be replacing the LPC Accumulator in this half of the valve body.

If you are replacing the 6 shift solenoid valves, study the shape of the valves and mark the package with the valve location they are supposed to be installed in. This will save time and confusion. There are 3 different shape valves for the 6 valve position. Some of the shapes are very similar and difficult to tell apart. Best to match each valve closely before reinstalling the new shift valve.

I did not take all the shift solenoids out at the same time, I took them out 1 at a time because they need to stay in the same location. Pay careful attention to the solenoid mounting clips when you remove them, the flat face of the clip goes against the valve body opening, not the valve. I put the clips for the solenoids back in without the wedges and only put the clips in about 1/2 way to hold the solenoids. This is because installing the clips with the wedges back in the valve body is DIFFICULT. Easier to do once the large separator place is reinstalled with the 2-T30 Torx screws and the valve body can then be flipped back over. Make sure you reinstall the 5 checkballs before the large separator plate is reinstalled.

A note on the separator plate alignment, there are roll pins to align the valve body halves and the separator plates, BUT the roll pins are not located in the top half of the valve body (portion that has the shift solenoids) and if you do not align the large separator before installing the 2-T30 Torx bolts, you will have a problem getting the 2 valve body halves back together. I used a tapered punch to carefully alight the 2 holes where the roll pins pass thru the separator plate before tightening and torqueing the 2- T30 Torx screws. You may need to play with this a bit and test fit the other half of the valve body to make sure the halves drop together easily before moving on.

Picture of the small Aux valve body roll pins, I did not take close ups of the main valve body roll pins.

Now onto the shift valve clips with the steel wedges. The steel wedges are to add additional support for the 6 shift valve, the wedges go inside the original spring clips. Once you have the large separator plate bolted back onto the upper valve body half, you can now flip it over. Now you can pull each shift solenoid spring clip out one at a time and insert the steel wedges and then reinstall the solenoid clip. Make sure to put the flat side of the clip against the valve body, not the solenoid. You will need a small hammer and a small block of wood or dowel rod to tap these clips in and seat them flush. This is true for all the solenoid clips except for I think "Linear Solenoid B". The sheet metal strap that bolts on the end of the valve body that has the 6 solenoids has a tang that extends down into one of the solenoid clip cavities that will require that specific solenoid clip to be seated below the valve body half. You can either use a small punch or screw driver to tap the clip lower so the sheet metal tang will not bend or cause the bracket not to sit flush on the end of the valve body.

Once you start to reassemble the valve body halves along with the separator plates, keep in mind there are 2-4 bolts that are under the wiring harness or under the Aux valve body that will need to be installed and torqued before the wiring harness can be reinstalled.

Here is a picture reassembled valve body ready to go back into the transmission. At this point I would suggest you clean off the valve body bolt hole arrows and use a black Sharpie marker to highlight the bolt locations. I also marked the filter bolt areas with a Sharpie. I found that since the valve body is heavy and you need to guild the electrical connector in before pushing the valve body up in the transmission, I just used the filter bolt holes to initially hang the valve body in place as these were the easiest and most centrally located bolts to use.

Get the proper length bolts in the correct location. Install the new bolts with the sealer in the proper locations. 2 of these bolts with sealer hold the small sensor on the edge of valve body, so this is an easy reference, then find the correct location for the 3rd bolt with sealer. Once you do this, there are only 4 other bolts to properly locate other than the filter bolts.

Diagram for location of replacement bolts with sealer. Some versions of the transmission may have an additional shorter aluminum bolt that needs to be installed, it is very much like the aluminum filter retaining bolts but shorter. Not sure exactly which version/model of the transmission requires this 3rd shorter aluminum bolt.

Push the valve body up with 1 hand while positioning it correctly. I would pick out 2 of the longest bolts, possibly the filter bolts, and use these to "hang" the valve body in the transmission by hand tightening these bolts about 5-6 turns, this will then free up our hands to find the correct bolts and get the valve body aligned and seated into the body of the transmission. I think there may be some locating pins that may need to be engaged? Once valve body has been positioned against the transmission verify correct bolt lengths and make sure you re-install the small sensor near the Aux valve body. I again used a taper punch alight the sensor holes. Then it is time to torque the valve body bolts in a 3 stage sequence. Quadruple check the bolt torque before installing the filter. Make sure you carefully and slowly torque the filter bolts. I did not do the torque angle method on these bolts, just torqued them 88 in/lbs. I was a bit worried about these because they are long aluminum bolts but they finally reached the 88 in/lbs.

This was all from memory, hopefully it is accurate and helpful. I will edit and update as needed.

 

[jfoj]

Finally received additional fluid and topped up fluid level in the transmission. The great thing is you can use the Remote Start feature on the keyfob to start the engine and shut it off. Since the fill plug is near the exhaust, I loosen the fill plug almost all the way, remote start the engine, quickly remove fill plug and while the engine RPM is coming down I get the fill hose in the transmission. Slowly fill the transmission until the fluid starts to drain out the fill plug WITH the engine running. Sneak the fill plug back up being careful of the exhaust that is warming up, thread the fill plug in at least 1/2 way of fully before holding the Remote Start button on the keyfob to shut the engine off. Then make sure to fully tighten the fill plug, again be careful of the warm exhaust.

As for tools, here is a picture of the tools used for the job. Again, this is on the V8 engine, so for the 3.0l Diesel or the HD 2500 trucks or heavier you may not need to remove the drivers side upstream O2 sensor and drop the exhaust down.

1/4" Drive Torque Wrench
1/4" Drive ratchet
1/4" Drive extensions
1/4" Drive T30 Torx bit
1/4" Drive E20 Torx socket
1/4" Drive 8 mm socket
1/4" Drive 6 mm Hex bit for PPE aluminum trans pan bolts (only if you install PPE pan)

8 mm Hex bit for trans fill plug, I happened to have a 8 mm to 3/8" Hex bit so I used this short bit with my long 3/8" ratcheting box wrench, this worked very well for how tight the transmission fill plug was.

2 long flat blade screw drivers to remove O2 sensor connector lock and release the O2 sensor connector

2 small flat blade screw drivers to manipulate and help remove transmission valves

2 hook tools to unlatch the electrical connectors on the valve body and to manipulate and help remove transmission valves

7/8" O2 sensor socket for oxygen sensor removal

For exhaust nut removal

3/8" Drive long flex head ratchet
3/8" Drive wobble extension set, this is a 4 piece Craftsman set from Lowe's
3/8" Drive 15 mm deep socket
1/2" to 3/8" drive adapter because I did need to use my long 1/2" swivel head ratchet to break 2 of the exhaust nuts loose because the flex extensions cause you to loose some torque on the socket.

I used a shallow plastic mixing pan (not pictured) from Lowe's/Home Depot found in the concrete section as a drain pan, these things are like $8 and have a large footprint so they easily can be put under the transmission or I also use them for cooling system work to catch fluid.

Small Mixing Tub

 

[jfoj]

As to anyone wondering why myself or others may be paying for this out of our pockets, we are buying RELIABILITY!

The thing is you never known when the valve body will crap out on you or cause the rear wheels to lock up. The OE valve body will also start to prematurely wear the transmission clutches and torque converter due to pressure leaks and flared shifting. This is a pre-emptive strike to hopefully extend the life of the transmission.

The other problem is at this point in time if you have a valve body failure, you may be waiting 1-2 months for parts. We have had members here waiting for 4 months for parts!

Even if the part problem is resolved and you can get a valve body quickly, it is pretty much the same crappy REBUILT valve body without any real or decent improvements. Might actually be somewhat worse than your valve body when new.

Make your choices and decide how you want to spend your time and money. I decided to buy RELIABILITY at this point and I can already tell there is an improvement over the OE valve body performance and it had not "failed" when I performed the upgrades.

 

[viven44]

Kudos to you for doing this and getting this done right, many including myself would probably not have the guts to attempt this on a vehicle under warranty. We have many spare classic clunkers at the house so 1-2 month wait is no big deal.

If this is an issue on our vehicle (sounds like it could be at some point)
- during warranty - let the dealer address this to get us some life out of the unit. The rate at which we use it (~6-7K miles) per year it would be the years first out of warranty.
- post warranty - I would probably get a full rebuild on the transmission depending on the mileage... sounds like about $5500 at my local shop

At any rate this tutorial is very helpful, so thank you for posting the details.