GREAT video, Nick. We gotta play detective every time we tear one down, to make sure we not only address common problems and updates, but also to fix the specific cause of the failure of that particular unit. You did a great job on this one. I'll be looking forward to more like this!

@nickstransmissions

5 ай бұрын

Thank you, Kevin - appreciate the feedback as always! There will be at least one more 4L60E Autopsy vid coming soon...

Very good video, you are the best at explaining parts failures and teaching what to look for.

@nickstransmissions

5 ай бұрын

Thanks, Wilburn! Appreciate the kind words.

Excellent as always!

@nickstransmissions

5 ай бұрын

Thanks, HMG!

Great video Nick, Thank You.

@nickstransmissions

5 ай бұрын

Thank you, Marty! Appreciate it.

Great video Nick! Is there a possibility that this vehicle was towed without the engine running?

@nickstransmissions

5 ай бұрын

Thank you, Dave! Great question - I'll follow up w/the customer and report back.

There is no doubt that it is a lube problem. Stevie Wonder doesn't have to wonder. If the Viton seal appears OK, the the next point of contention is the last sealing ring on the input shaft. If that is OK, then there is a flow problem either in the pump or the cooling lines/rad cooler. A faulty forward piston housing will/may stop the forward motion but it will not affect the lube circuit. A faulty bottom sealing ring will affect both the forward apply and the lube circuit.

@nickstransmissions

5 ай бұрын

The forward clutch burn up was caused by the mid-case failure, specifically metal debris getting into the housing, scoring it up and cutting material from the lip seal portion of the piston. And I agree, a lube failure of some sort best fits the evidence...Was my first thought once I had the gear train and sun shell out of the case. The underlying cause is anyone's guess but restriction in the internal transmission cooler and/or lines is usually what causes these problems.

Do you have an e mail?

@nickstransmissions

5 ай бұрын

Hi Larry, you can contact me on Tahoeyukonforum.com via direct message; I have the same user name as here...If you have a general 4L60E transmission question, please post it here so others can view the response.. Otherwise if you want to inquire about having a transmission rebuilt, contact me via Tahoeyukonforum.com and we can go from there. Thank you for watching!

@larryschaum6280

5 ай бұрын

@@nickstransmissions No. I just wanted to discuss this one with you. But here is fine. I have ran into this before. I will say that, in my opinion. You have a pretty good grasp on the problem. The ones that I have seen have been do to the cooler not being flushed. The last hole in the output shaft supply’s lube where the problem manifested. I have found that last hole restricted or completely blocked from debris before. I have also seen that lube hole blocked when debris, from failed clutches makes it way there. In GM’s infinite wisdom. The lower end is the last thing lubed. Not sure of the exact number here. But about 30%! Of the fluid passes through the cooler at a given time. Before the process starts again. The last lube hole in the shaft is also the smallest. So that’s when the lube circuit can’t keep up. At least in what I have seen. Opinion?

@nickstransmissions

5 ай бұрын

Makes perfect sense to me, and agree with your assessment. Most of GMs transmissions have the same general lube circuitry design and associated inherent weaknesses...I imagine that they would have moved to a center-lube design for the 4L60E if case components supported such an engineering change but unlike the 4L80E, which has a large central object that's already capable of routing fluid (just needed a minor re-design to meeting overall engineering intent), the 60 and it's ancestor, the 700R4 lack such a suitable object...The 60's center support simply can be tweaked to route fluid... Thus, flushing lines and coolers before installing a new transmission is so crucial for ensuring no problems like this happen. This vehicle was used for towing and off-road use and there was some minor signs of stress to the coast clutches that may or may not have been sustained before the melt-down. So that's one potential source of debris/material that could have partially restricted flow to the gear train. Once lube was restricted, the rest of the dominos fell... I'll be doing more of these "failure mode and effect analysis" type videos going forward, including all different transmissions. What will distinguish them from regular tear down vids will be the post-clean up analysis portion that's contained within this video where we closely scrutinize the damaged parts, trying to solve the puzzle before tossing them into the scrap bin. Thanks for watching and your input, Larry!

No load springs

@nickstransmissions

5 ай бұрын

Hey Pat, thank you for watching...Is that why you think the melt-down occurred?

@patruddiman4228

5 ай бұрын

I have no idea but I watch enough transmission videos most rebuilders always say to put them back in.

@nickstransmissions

5 ай бұрын

They aren't needed unless clutch clearance is below .035 and RPMS are expected to exceed 5500 on the regular...Plus you can install Transgo's high rate return springs, which are the better way to go for centrifugal apply prevention and performance improvements. Additionally, official industry guidance on that issue is mixed; some publications say to put them back in while others say to leave them out... Your comment "no load springs" didn't really tell me what you were getting at, other than perhaps making an observation hence why I asked... Regardless, thanks again for watching; I appreciate the viewership.

@patruddiman4228

5 ай бұрын

@@nickstransmissions I was just making a observation I guess.

@nickstransmissions

5 ай бұрын

Roger, that - please subscribe if you haven't already as I'll be doing more vids on 4L60Es, 80s and 6Ls in the very near future. Cheers!