Quick and partial update.
I finally had to send the family away for 3 weeks so I could get on this project!!! And now it is 95F!!
Well the ROYAL PITA is the exhaust MUST be dropped to get the trans pan out. The exhaust cross over "Y" pipe it only about 1" below the trans pan and there is NO WAY to get the trans pan out without dropping the exhaust from the manifolds. The "Y" pipe only need to be unbolted from the exhaust manifolds and dropped down about 2 inches, this is not a problem because there is a flexible exhaust section that allows the "Y" pipe to drop down. Just getting to the flange nuts and breaking them free is a PITA.
Depending on how old your vehicle is and what climate you operate in, removing the exhaust down pipe nuts could be a challenge. My vehicle is less than 1 year old and about 8700 miles on it. Nuts came off pretty easily, but a few were tight and I had to bounce/spring/jerk the ratchet on a few of the nuts to get the to initially bust loose. The 3 extensions flexed quite a bit, so I had to get the nuts to break free with some creativity. WD40 or penetrating oil is really needed because the studs are about 1 inch of exposed threads and the nuts will come off the studs much easier with some sort of lubricant.
This exhaust cross over really will make is a PITA for anyone to change the trans fluid on these trucks. I think the 3/4 ton or 2500 series have more space and the exhaust may not be an issue. The 2 wheel drive vehicles may have a different exhaust "Y" pipe configuration, I have not had to a chance to look at one. But the 4 wheel drive units are not going to be easy to drop the trans pan on the exhaust "Y" pipe needs to be fully unbolted from both exhaust manifolds. If you have an AT4 or a Z71/ZR2 with skid plates this may make it even more fun??
So what does that involve!!!
I have a set of Rhino Ramp MAX rated at 16,000 lbs. If you are dealing with plastic ramps, get the heavy duty versions, you only have 1 chance! Put the truck on on the ramps.
Word to the wise, TURN OFF the A/C before you start the vehicle and put it on the ramps, the A/C drain drips right along the drivers side of the trans and you will not want it dripping on you while under the vehicle. I would put the truck on the ramps the night before so you will have cold exhaust to work around.
Before you do anything, make sure you can get the transmission fill plug loose on the drivers side rear of the transmission. If you cannot fill the transmission after you drop the pan you are in trouble!
Transmission fill plug is 8mm hex. It is tight to the front driveshaft on 4 wheel drive models. You might be able to but a 8 mm box wrench on the front of a 3/8" drive 8 mm hex bit and avoid the tight space where the front driveshaft it. NOTE - Break the trans fill plug loose before you do ANYTHING else. If you cannot get the fill plug to break loose or strip it, you have a problem, so do not remove the trans pan until you get this part addressed. I had a 8 mm hex bit that necked down to 3/8" hex that was really short that I used one of my very long 3/8" box wrench on to break the fill plug loose, it was rather tight or firm to break free.
Fluid level - this is a highly loaded and contentious issue. With the front up on ramps but the driveway has a slight dip to the truck is closer to flat that fully elevated on the ramps. With the vehicle cold and the engine not running, once I broke the fill plug loose and partially remove it to see if fluid would come out with the engine not running, it did. So put the plug back in and started the engine. Made a dipstick out of a piece of white insulated 14 gauge Romex bend to verify the level with the engine running from cold start. Once engine RPM dropped, removed the fill plug with the engine running and no fluid came out. Put the "dipstick" I made up in and found the level was just at the drain plug, so this is how I am going to refill the transmission.
Not playing games with 175F fluid temperatures and cherry red exhaust "Y" pipe in close quarters, this is just asking for problems. I will fill the trans cold until it starts to drain out the fill, start the engine with the keyfob while I am under the car and then top the fluid level up until the it just starts to trickle out the fill plug, button it up and shift it through the gears and then let it cool off and check fluid again. Top of again if needed, then drive and fully warm up and get about 10-15 miles on the truck and bring it back, put it on the ramps and check the level again the following day once it has cooled off.
I will be removing the cooler thermostat from the valve body, but I cannot see that the cooler would drain if you are just changing the fluid and filter. Additionally I have yet to see my trans temp go above 165-168F so I have no idea if the cooler thermostat has ever opened anyway. The cooler may drain while the valve body is out, but I will be bypassing the cooler thermostat so this is a non issue anyway.
Remove the drivers side pre-cat O2 sensor! It is directly in line with one of the manifold studs and there is no way around the O2 sensor, it must be removed, not too bad, the wire lock and connector are probably more of a problem than O2 sensor removal if you have a O2 sensor socket. The O2 sensors are 7/8" but there is no way to get a box or open end wrench in there, just get the O2 sensor socket. You can usually rent/borrow the O2 sensor socket kit from local auto parts store.
Carefully removing the white locking tab from the O2 sensor connector and disconnecting the connector. This requires a few long narrow flat blade screw drivers and contorting to get the connector apart.
The slide the O2 sensor socket up over the sensor, I used the medium depth socket that had the 1/2" drive side connection. I have a longer flex head 1/2" torque wrench that allowed me to get in and pop the sensor loose, it was not too difficult to break free, much easier than the exhaust manifold nuts.
3 - 3/8" drive wobble extensions and a 15 mm deep socket. I have a Craftsman 3 piece wobble extension set that I purchased at Lowes a number of years ago. There are 3 different length extensions. I had to use all 3 for most exhaust nuts, I sometimes needed the short extension up against the socket in some of the more tricky areas.
I will update the thread with some pictures, a tool list and comment on any other fun things to deal with. I think the exhaust will be a bigger problem than dealing with the valve body at the end of the day.
If your vehicle is over 2 years old, I would order new exhaust downpipe nuts, 6 required and I would use a generous amount of anti-seize on the studs because to perform a transmission service the exhaust "Y" pipe will need to be dropped down on most models. I can see a lot of transmissions not getting services due to this exhaust clearance problem.
I am putting a PPE aftermarket aluminum pan with a drain plug so I can at least drain the transmission on a regular basis. This pan hold an addition 2.5 quarts of fluid as well.
What struck me at interesting it the trans pan does not hold a lot of fluid. The valve body and 2 fluid pumps take up so much real estate I do not think more than 3 quarts came out when I pulled the pan. I will try and get a better measurement, but it just did not seem like a lot of fluid comes out with a pan drop.
So back to the heat and to get the valve body pulled out. Probably will get the valve body out later today when it cools off a bit and tear into it tomorrow when I have not been baking in the heat fighting with the exhaust!
I think what I will find is for anyone that can drop the exhaust "Y" pipe should be able do do the valve body work. I think the valve body will be easy when compared to the exhaust nightmare.
More to follow.
