I have a recently rebuilt and upgraded 4L60e and it just started acting funny. It is fine when cold, but after the car warms up it slips in fourth gear when you put your foot into it , and it slips and taps the rev limiter when shifting from 2nd to 3rd. I realize that this could be bad clutches but with the high quality of clutches we put in this thing and being it only has 1500 miles on it behind basically stock motor, i am wondering if it could be an ELECTRICAL PROBLEM like a solenoid or something, and if so will it throw a ses light. Thanks Prorac1

 

Could be the OD sprag. When I had my 700R4 rebuilt (same tranny just not electronically controlled) I broke it in for about 500 miles and romped it, the motor grabbed for a split second then free spun to redline. Took it into the guy he said the OD sprag had broken. Then the guy tried to blame in on me for getting on it...Yeah my 305 broke a new 700R4 tranny because I abused it... I don't think so...so I did my homework, come to find out he didn't replace that part like he should have, it ended up going out. They're pretty weak and if you ever see one it's pretty amazing that little thing can handle all that power. That sounds like what your problem could be.

 

Sounds like something was not done right. I just had mine rebuilt and they upgraded the band and sprag and put more clutches in it.
I have found out through research that ALOT of guys don,t know how to rebuild these trannys the right way, they may say they do but it is hard to find a good overdrive tranny man.
I have a friend who had a 94 supercharged putting 575 RWHP and he went through 4 tranny guys before he found someone to build a 4L60E to live behind that motor, one guy swore up and down he could do it and the tranny puked before the guy even got home.
Make sure the person doing the tranny knows whats going on make sure they have done alot of em and talk to the people that have had a tranny built by the guy you want to build yours.
I would be really pissed to have my tranny built after I went to all the work of pulling it out and putting it back in and it goes out in 1 to 2 thousand miles.

 

Your "Trans-Stop" shift kit has wiped out your 2-4 band.

Frank

 

No, It's not hard to find one...I'm right here. I've got 4L60E's in low 11 second cars that are not only working but they're lasting, too. I built my personal 700 over 2 years ago. It's probably got around 200 quarter mile passes on it. The car runs 12.82. I built Dirks (RACINLT1)s 4L60E over 2 years ago, and it runs 11.2 on the bottle.

Frank

 

How does the shift kit wipe out the 2-4 band, and could it still
be it when 2nd gear is so strong. Plus it only does it when it is cold. Ill go through a typical run when warmed up for you so you get what im feelin. First gear (besided not having any traction) pulls and runs good, hits a good SOLID second gear and runs out second good, than when it revs out to shift into third it slips and taps the revlimiter going into third and slides into third, at which point you let off the gas, letting it shift into 4th, than when you drive in 4th its find till you give it a little gas than it slips back into 3rd, (and i mean SLIP) Hope this helps, thanks for all the help guys, prorac1

 

Trans-Go shift kits always burn up the 2-4 band and the 3-4 clutches. It sounds like it's done BOTH in your case. I'll bet the fluid smells nasty, and is black???

Frank

 

I agree that it acts like that, but my fluid is bright red, and smells like new. The trans temp did get kinda high indicating a slipping condition. The tranny is now out so ill keep ya all posted, i think your right, but i hope not, lol. So what to do, how do i remove the trans go and what kind of shift kit should i install. Thanks, prorac1