Ultimate 4L60E Parts List

[Matthew Jeschke]

I'm getting some hard earned experience building 4L60E. I hand built and installed mine in (2022?). Worked beautifully even with my build 6.0L LQ9 (450hp??? certainly gobs of torque down low). Well I blew it up (teardown thread here).

When you comment please let us know your experience working on the 4L60E. Originally when I built my first 4L60E it took nearly a YEAR to compile my build of materials as everybody on the unnamed forum w/o experience wanted to chime in. It's okay if you want to add some input but please let us know from where that knowledge comes (direct experience or otherwise).

Lets cut to the chase, I have to open the case up and want to see if there's anything to consider upgrading in the process. My original build of materials list is HERE. I'm also trying to compile my build notes HERE. These posts are EVERYWHERE on the internet. It's too much to sort through though. I'd like one here with the ULTIMATE parts. You can pick and choose what to use from there.

I DON'T BELEIVE IN SHIFT KITS NOR MODIFYING THE VALVE BODY. I PREFER A VALVE BODY THAT FUNCTIONS AS FACTORY INTENDED. THIS MAY REQUIRES SOME KNOWLEDGE OF TRANSMISSION TUNING.

Running Parts list I'm going to update the chosen parts here so they are at the top of this thread.

CASE:
4L60E OEM
Reverse Input Drum OEM
Shell Sonnax
Sun Gear with Sonnax wide bushing
Servo OEM Corvette Servo
Accumulator Pistons Sonnax Pinless
- Springs Sonnax

Low Reverse:
Clutches Borg-Warner
Steels 5 x Turbulator "low Drag" 0.068"
Waved Steel OEM
Band Borg-Warner Hi-Energy Wide 2-4 band

Valve Body
Factory OEM
Separator Plate Transgo
Manifold Pressure Switch
Accumulator Sonnax
- Spring Sonnax
Shift Solinoids OEM
PCS OEM
Checkballs Sonnax

Reverse Input Drum
Clutches Borg-Warner
Steels
Waved Steel
Band

Pump
Factory
Rotor
Spring
Stator Sonnax
Wiper OEM
Pivot Pin OEM
Boost Valve Transgo

Input Drum
Forward Clutches Borg-Warner
Forward Steels
Overrun Clutches Borg-Warner
Overrun Steels
Pressure plates OEM
Apply plates OEM
Snap rings OEM
3-4 Clutches Raybestos
3-4 Steels Raybestos
Forward Sprag Borg-Warner
Piston Return Springs OEM
Teflon Input shaft seals OEM
Drum Reinforcement Sonnax
3-4 piston OEM
Overrun piston & Sleeve OEM
Seal input shaft Locktight


Hard Upgrades
Input Shaft Sonnax
Output Shaft Sonnax
Pinion OEM
4L79 Input Drum 4L79
Sonnax Parts
Torque Converter OEM


MODIFICATIONS:

Bore pump drain back to 5/16"
Sun gear fluid relief cuts

I didn't do these modifications on my original build. Not sure if I want to do them now. My truck seldom if ever see's over 4k RPM, mostly lives between 1500 and 3k RPM. I've also split hairs on maintaining optimal MPG / efficiency. I have to study if these will reduce drag on the pump itself... I think so? I which case despite not running high RPM I may be interested in doing these. Another consideration here is ATF temp. Operating temp for Dextron VI is around 180F. It's actually tricky to achieve this temp which results in optimal viscosity (without damage to trans). I think over 200F, certainly over 225F and we're starting to get into areas where transmission is at risk. Note: I tuned with this in mind to protect transmission at 225F+ ATF. Also the temp sensor doesn't seem to capture issues in case with over temp. If the fluid is HOT then it may already be too late. I blew out my low reverse and the ATF temp on dash never exceeded 180F. I only noticed due to smell and feeling the slip.

 

[Matthew Jeschke]

@NickTransmissions videos are great. I'm going to reference some of them here and check against my previous parts list.

TESTING​

Another concern I have is I don't have a vacuum tester to validate operation of the pump and valve body. I did build a fixture to pressure test the valve body with a mity vac hand pump. It worked but didn't produce similar test results to an active pump pulling a vacuum constantly... Ultimately I poured ATF into the various parts of the valve body (following Sonnax diagram for different valves / testing). I watched to see if the fluid leaked out. I may build a test fixture from a piece of billet aluminum so I can actually hook my vacuum pump up and test correctly... Or just have a trans shop test the valve body and pump. I kind of want to build these on the side for people though.

Forgot to mention to be more specific, I diluted the ATF with a solvent (I forget which) when I did the valve body test to simulate it's viscosity at higher temp. I then let it sit overnight with a cover on it (to prevent flash off of the solvent and looked at it the next morning.

 

[NickTransmissions]

@NickTransmissions videos are great. I'm going to reference some of them here and check against my previous parts list.

TESTING​

Another concern I have is I don't have a vacuum tester to validate operation of the pump and valve body. I did build a fixture to pressure test the valve body with a mity vac hand pump. It worked but didn't produce similar test results to an active pump pulling a vacuum constantly... Ultimately I poured ATF into the various parts of the valve body (following Sonnax diagram for different valves / testing). I watched to see if the fluid leaked out. I may build a test fixture from a piece of billet aluminum so I can actually hook my vacuum pump up and test correctly... Or just have a trans shop test the valve body and pump. I kind of want to build these on the side for people though.

Thank you for the views and kind words, Matthew.

If you plan on building pumps and/or transmissions for the public, having a vacuum test set up is mandatory, in my professional opinion. I can't imagine doing my job without it as I have caught so many issues/problems that would have reappeared in my builds without the testing.

The test kit itself looks to be under $300.00 from places like Summit and JEGS...Add another 12-15% or so for state sales tax (if applicable) and shipping costs (if not free) but it's well worth the money...Will pay for itself in only a few jobs...

 

[Matthew Jeschke]

I put up an ad to see if anybody would like a custom 4L60E build (using my recipe) and immediately got multiple requests. However, I told them no as I wasn't confident in my ability having built only one! I'm 100% with you on having the test systems. The gentleman who helped me build mine has built hundreds of them but doesn't have that stuff. It makes me darn nervous not knowing though so I came up with those tests to verify as best as I could w/o proper tools.

I've been watching your videos. IMO they're the best ones out there on building these. It's very kind of you to be so transparent. I created a thread during my build years ago and the big shops chimed in telling me I'd not be able to do this. Yet despite all that the transmission worked and well... I'm not to the point of knowing if mine blew up as a result of faulty build (I'm thinking not as I had 5 years on it and 40k miles?) or simply due to running hydraulic system dry.

Long story short, thanks for sharing your knowledge Nick!!!