Rebuilt transmission problems... Again...

[rolfsent]

So the 4L60E in my 97 Yukon crapped out on me about a month or two ago and I had it rebuilt by a reputable shop near where I live. About 2 weeks after it was rebuilt my OD was back to having problems and 1-2-3 shifting was rough. So it was pulled out of the truck and repaired under warranty. Now not even 2 weeks after that my trans is consistently shifting hard out of first into second. It's not shifting bad or having any other problems but when it shifts it jerks the whole truck. Any ideas on what the hell is gong on? I'm at my witts end with this transmission and I'm sick of taking it back to get pulled out every two weeks!

 

[SunlitComet]

check to tps for smooth continuous sensor readings. and strongly considered getting a second shop to look at it wit a different set of eyes. i kinda remember there was a adaptive learn reset for only when a tranny is overhaul. done as a dealer function maybe. one other thing is that there are codes, tranny included, that do not activate the CEL. check for stored or pending codes to see if a solenoid is screwed up.

 

[gpracer1]

Do a google search for hard 1-2 shift. Could be the check ball has blown through the valve body plate or is missing, accumulator problem (easy to check), and a few other things.

 

[retorq]

Maybe they altered the force motors that control the shifts ....

 

[SunlitComet]

i actually got the hard 1-2 shift straight out of the tranny shop overhaul.

 

[purple 'hoe]

Dumb question, but did they put a shift kit in for you? Seems a little harsh of a shift for just a shift kit though. I never remember mine jerking the truck at all unless I was at 75% or more throttle

 

[Donnie Yukonie]

this sounds like the exact problem i had , id bet when they rebuilt your trans they didn't put in a new Torque converter . thats what it sounds like to me hard shifts after the trans warms up? no matter if you baby it right?

 

[rolfsent]

this sounds like the exact problem i had , id bet when they rebuilt your trans they didn't put in a new Torque converter . thats what it sounds like to me hard shifts after the trans warms up? no matter if you baby it right?

The torque converter is new and was replaced when it was rebuilt. It seems to happen more after I've been driving for a while.

---------- Post added at 10:54 AM ---------- Previous post was at 10:52 AM ----------

i actually got the hard 1-2 shift straight out of the tranny shop overhaul.

So is not something to worry about? I actually just realized my dads Silverado has the same thing happens from 1-2. Maybe it is just a shift kit??? I'm gonna go through the paperwork again to see.

 

[SunlitComet]

My understanding is that someone else had tried to do a shift improvement kit in it before and either messed it up or did not complete it and it jacked up the tranny pressures so high that eventually it cracked a piston and started the tranny chattering as i was leaving California. while the problem was corrected to no happen again the hard shift may be another side effect of the shift kit gone bad or if that adaptive thing has something to do with it.

 

[retorq]

My understanding is that someone else had tried to do a shift improvement kit in it before and either messed it up or did not complete it and it jacked up the tranny pressures so high that eventually it cracked a piston and started the tranny chattering as i was leaving California. while the problem was corrected to no happen again the hard shift may be another side effect of the shift kit gone bad or if that adaptive thing has something to do with it.

If that was the case who ever tore it down and rebuild it could have put in OE springs and what not to get it back to factory. It wouldn't have been that hard. The only mod that I can't undo while currently into mine is the hole that I drilled in the low/reverse piston which is $15 for a new one.