Tales from the Trans Bench

Joined
Dec 19, 2013
Messages
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Location
Fort Worth, Texas
Not too long ago, I swapped a LQ4 6.0L into a 2003 Chevy Tahoe for a customer to replace the leaky/noisy LM7 5.3L, I advised him that the stock 4L60E will last however long it lasts. He called me yesterday & said it was slipping at full throttle. He brought it in & I confirmed it was in fact flaring during the 2-3 shift under full throttle.

Advised him to take it easy 'till we can get a 4L65E built for it as he didn't want to do without his truck for a unknown length of time for me to build his original unit to 4L65E specs along with my upgrades as parts can be severely back ordered right now. I'd rather put used OE 4-Pinion Carriers in than new Chinese 5-Pinion Carriers! Pure Garbage. It's not me pushing 5-Pinion Carriers either because 4-Pinion Carriers would hold-up just fine in this application.
He frequents internet forums & is convinced he needs them, Who am I to argue against ME making more money?

I did him one better......I found a Real 4L65E out of a 2004 AWD LQ9 6.0L Escalade at a local yard that I deal with often. They wanted $850 with a 90 day warranty.....Got it for $500 cash with NO warranty. This was a calculated risk on my part as it could've been completely bombed out & I'd have to eat it.....This gamble paid off as it's in near perfect shape for rebuilding.

The disturbing part is, It was on the very edge of the Sun Shell splines stripping out. Would've lasted 10-20,000 miles at most, Would've sucked for someone to put this in a AWD Escalade/Denali/Silverado SS & have it fail (Most likely out of the warranty period?)

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Latest hardened GM 4L65E/4L70E Reaction Sunshell, This unit is actually getting a Sonnax Smart Shell, But this illustrates how far gone the splines are on the one above!!

My gosh, that's bad. Where they not manufactured correctly/wrong steel used? Is this a known/common problem?
 
That's some of the same stuff the dude over at Precision Transmission talks about. Nice to see another angle on it!! They had one the other day where the first drum (Whatever its called) had started to flare out and chew through the case. Never knew something like that could happen.

It's certainly interesting for those of us who understand how they work, but wouldn't touch rebuilding/working on/fixing one in a million years.
 
They were known for the splined part breaking off the sunshell on 700R4/4L60 & the early 4L60E's, Then they softened the sunshell & spline strippage became the new mode of failure. It's actually odd to see this on a 4L65E that's in otherwise really good shape. But I don't know the history of the unit.....I'd be curious if it had a harsh 1-2 shift.
 
That's some of the same stuff the dude over at Precision Transmission talks about. Nice to see another angle on it!! They had one the other day where the first drum (Whatever its called) had started to flare out and chew through the case. Never knew something like that could happen.

It's certainly interesting for those of us who understand how they work, but wouldn't touch rebuilding/working on/fixing one in a million years.
The Reverse Input Drum.....The Drive Lugs can flare out & cut the barrel of the case, Sometimes all the way through. Takes some high sustained RPM in 1st gear & is not at all common. I bet that unit had a aftermarket Shift Valve that allows Manual Low at any speed or a Tune that allows it.
 
The Reverse Input Drum.....The Drive Lugs can flare out & cut the barrel of the case, Sometimes all the way through. Takes some high sustained RPM in 1st gear & is not at all common. I bet that unit had a aftermarket Shift Valve that allows Manual Low at any speed or a Tune that allows it.
I'd have to rewatch the video, but I'm pretty sure you're spot on and Richard said something about that. The tranny was completely trashed. Ate up the case there and closer to the back.



Lol, yep
 
Low quality parts . Even Amsoil won't help.
 
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Takes about 10 hours, I don't quite make my shop rate building transmissions. A labor of love that still puts food on the table during the slower Fall/Winter months.
 
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