I've built several of these so far.. The big issue with these units seems to be the valve bodies. On one I had to buy a remanned valve body as I just could not get the original to work. On the original VB I put in BOTH of the Sonnax Zip kits-main and tcc. The problem with the Sonnax Zip kits is that it does not have enough parts to fully repair the valve body. This vb has 6 shift control valves, and the zip kit only comes with 2 valves! When I vacuum tested my VB ALL of the shift control valves failed the vacuum test! ALL OF THEM! And yet the zip kit only has 2 valves total.. Transtar wants $60 EACH for those valves... You can easily spend $1000 (or more) buying the zip kits, and the tooling, and the reamer guide block, and still wind up with a valve body that is DOA... My local chevy dealership said the VB's are on national back order with no date in their system as to when they might be available again. This trans with the VB issues only had 42K miles on it.. Of the ones I've seen so far that have failed they have all been less than 90K miles... It's a disaster of a transmission and I recommend to my customers that they avoid those vehicles with this transmission if at all possible. I can't imagine there is going to be a supply of parts to keep these units running in the next 10 years. This unit is already obsolete and if you get stuck with one, it most likely is going to wind up costing you a LOT financially. Only used 2015-2019.. Currently a class action law suit on-going... RUN FOREST! RUN! Oh, and did I mention they have issues with the speed sensors and the wiring harnesses? Yeah, that too. The Sonnax zip kits are HARD to find as well.. My local parts house CANNOT get them at all... Forest, why are you still here? I told you to RUN!!!!!! Great video on rebuilding this unit. I think it's going to be like rebuilding a Model A pretty soon though..only with fewer parts available. Supposedly 800,000 of these poop-sicles were made... and I doubt there are enough parts to rebuild all 800,000 of them.. and EVERY one of them IS going to fail. And fail repeatedly due to VB issues. What's the long term solution if your valve body is COMPLETELY worn out by 42K miles? Do you want to rebuild the unit every 42K miles at $7000 to $8000 each time? No? Hmmm... The future is worse than bleak for the 8L90. I "liked" and "subscribed". Appreciate the hard work you put into making this video and how easy you make it seem. Takes me a full day to build one of these whereas I can build 3 6L80E's in a single day, and that includes machining the pump stator and bell housings.
Do you not deglaze your old steel plates? Every unit I’m in that’s getting a new set of frictions, I’ll deglaze the steels with a yellow roloc bristle disc. I feel like this helps the shifts adapt smoothly, along with better performance/shift quality. Same principle of people doing brake jobs and just pad slapping. I’m no GM guy, but any of my 10R/6R series, I’ll always deglaze when throwing in a fresh batch of frictions.
Good video though! I assemble dry on my units - afraid of attracting debris when assembling. Also, do you face your steel plates all a specific way, depending on clutch direction application? I try and install with the bevel side facing up, if the clutch is applying towards yourself. That way the flat side isn’t engraving into the grooves of the drum.
I put them in dry sometimes and never really see the problem with it. If the transmission is getting filled up full of fluid, it automatically primes the entire system within a couple of seconds once it fills a converter and everything gets soaked.
I recently seen a reel about Dave's Auto repair where you are discussing the diesel crank and 5-10sec go deal, I want to say I do not agree with that because imo oil is important to get to critical places before a load is applied to the engine.. Especially for the guys still running 15-40 it's thick and moves slowly..... Get some oil moving even if it's 2-5mins and you should be good to go.
Quick question if you can help it would be awesome. 2017 Escalade, hard 1-2 shift, other shifts seem ok. Two months ago there was a history dtc of p0747. Since clearing codes 3 months ago and almost 3000 miles, no dtcs, just a hard 1-2 shift. Fluid clean, no debris. Fast learn did not help. No availability on replacement valve bodies. My parts department basically showing nothing out there and nothing in transit. Looking at all the valve body parts from Sonnax, Transgo, and Superior. Parts get expensive pretty fast when you include the tooling and vacuum testing equipment. Can you roll your diagnostic dice on this one and tell me your thoughts?
Sonnax sure cure kit may help that, I have the same issue with no CEI 1,2 shift 80% of time is hard the rest is smooth, could it be because of high energy frictions installed.... Mine had the "updated" kit.
You make transmissions easier to
Understand
Thanks for this! You’re the man 🤌🏼
I've built several of these so far.. The big issue with these units seems to be the valve bodies. On one I had to buy a remanned valve body as I just could not get the original to work. On the original VB I put in BOTH of the Sonnax Zip kits-main and tcc. The problem with the Sonnax Zip kits is that it does not have enough parts to fully repair the valve body. This vb has 6 shift control valves, and the zip kit only comes with 2 valves! When I vacuum tested my VB ALL of the shift control valves failed the vacuum test! ALL OF THEM! And yet the zip kit only has 2 valves total.. Transtar wants $60 EACH for those valves... You can easily spend $1000 (or more) buying the zip kits, and the tooling, and the reamer guide block, and still wind up with a valve body that is DOA... My local chevy dealership said the VB's are on national back order with no date in their system as to when they might be available again. This trans with the VB issues only had 42K miles on it.. Of the ones I've seen so far that have failed they have all been less than 90K miles... It's a disaster of a transmission and I recommend to my customers that they avoid those vehicles with this transmission if at all possible. I can't imagine there is going to be a supply of parts to keep these units running in the next 10 years. This unit is already obsolete and if you get stuck with one, it most likely is going to wind up costing you a LOT financially. Only used 2015-2019.. Currently a class action law suit on-going... RUN FOREST! RUN! Oh, and did I mention they have issues with the speed sensors and the wiring harnesses? Yeah, that too. The Sonnax zip kits are HARD to find as well.. My local parts house CANNOT get them at all... Forest, why are you still here? I told you to RUN!!!!!!
Great video on rebuilding this unit. I think it's going to be like rebuilding a Model A pretty soon though..only with fewer parts available. Supposedly 800,000 of these poop-sicles were made... and I doubt there are enough parts to rebuild all 800,000 of them.. and EVERY one of them IS going to fail. And fail repeatedly due to VB issues. What's the long term solution if your valve body is COMPLETELY worn out by 42K miles? Do you want to rebuild the unit every 42K miles at $7000 to $8000 each time? No? Hmmm... The future is worse than bleak for the 8L90. I "liked" and "subscribed". Appreciate the hard work you put into making this video and how easy you make it seem. Takes me a full day to build one of these whereas I can build 3 6L80E's in a single day, and that includes machining the pump stator and bell housings.
Thanks, been waiting foe a good 8spd video, I will be referencing .
❤
Do you have a video or know of any good on a 4l80e? I have a 2005 Chevy 2500 4x4. Have done some 4l60e. Will be my first 4l80e.
I have 8L90 shifts fine when it’s cold but once it’s warm starts slipping from 1-2 and 5-6.
Is the clutch #4 going bad or Oils pressure issues?
Do you not deglaze your old steel plates? Every unit I’m in that’s getting a new set of frictions, I’ll deglaze the steels with a yellow roloc bristle disc. I feel like this helps the shifts adapt smoothly, along with better performance/shift quality. Same principle of people doing brake jobs and just pad slapping. I’m no GM guy, but any of my 10R/6R series, I’ll always deglaze when throwing in a fresh batch of frictions.
Good video though! I assemble dry on my units - afraid of attracting debris when assembling. Also, do you face your steel plates all a specific way, depending on clutch direction application? I try and install with the bevel side facing up, if the clutch is applying towards yourself. That way the flat side isn’t engraving into the grooves of the drum.
What Piston/spring compressor are you using?
How do you feel about putting clutch’s in dry?have you seen any research on that being harmful?
I put them in dry sometimes and never really see the problem with it. If the transmission is getting filled up full of fluid, it automatically primes the entire system within a couple of seconds once it fills a converter and everything gets soaked.
I recently seen a reel about Dave's Auto repair where you are discussing the diesel crank and 5-10sec go deal, I want to say I do not agree with that because imo oil is important to get to critical places before a load is applied to the engine.. Especially for the guys still running 15-40 it's thick and moves slowly..... Get some oil moving even if it's 2-5mins and you should be good to go.
Quick question if you can help it would be awesome. 2017 Escalade, hard 1-2 shift, other shifts seem ok. Two months ago there was a history dtc of p0747. Since clearing codes 3 months ago and almost 3000 miles, no dtcs, just a hard 1-2 shift. Fluid clean, no debris. Fast learn did not help. No availability on replacement valve bodies. My parts department basically showing nothing out there and nothing in transit. Looking at all the valve body parts from Sonnax, Transgo, and Superior. Parts get expensive pretty fast when you include the tooling and vacuum testing equipment. Can you roll your diagnostic dice on this one and tell me your thoughts?
Sonnax sure cure kit may help that, I have the same issue with no CEI 1,2 shift 80% of time is hard the rest is smooth, could it be because of high energy frictions installed.... Mine had the "updated" kit.