You may want to check out this thread:

https://ls1tech.com/forums/ls4-front...e-project.html

It's what I did to reduce the liklihood of another trans failure.

 

transmission is now rebuilt due to boost valve and torque converter failure. so add me to the fail list please.

 

Filed my second complaint. Last time i didnt put the VIN# in so this time i got it.

 

Got the car back this weekend. They replaced the shift solenoid after it was sticking @ 105psi between .6-.8 amps. Seems like it shifts nicer but time will tell.

 

Ahh. Just noticed this thread. I have the same issue as many of you. My tranny tends to slip when stopped at a light and then trying to go and also sometimes under high load in the upper rpm's. Do we have a fix for this yet?

 

Adamcc91 transmission slipping and shifting hard

 

I was driving to class this morning, went to pull away from a stop light, and everything felt normal until about 15-20 mph. Then the revs went up and my impala slowed down. Didn't make it much further before I pulled into a parking lot. Give it juice, but no go. 2006 Impala SS, 66500 mi. Original trans.

 

Oh yeah, I forgot to add that my 5yr./100000mile warranty ends in exactly a month....like clockwork. Good thing this happened while it did.

 

There is a fix, however, it's not from GM. Check out some of the other transmission threads on this site or on gmls4.com to learn more about what can be done to improve our transmissions.

Added you to the list.

Added you to the list, too. Let us know how the dealer handles it!

 

Well had to go in to the shop today to get some things out of my car and got to see all the pieces of my trans that were shattered and/or melted together. One of my planetary gears was shattered into 4 pieces alone...good thing dealer is covering all work under warranty. Even got a rental impala to drive around in the meantime. Its got the 3.5 though..I miss my ls4 already

 

Wow...That's not a very common failure for a stock LS4. You got lucky!

Make sure they replace the torque converter, as it may have some wear due to this failure, and the angry converter relief valve.

 

Okay thanks for the advice on the converter. I already have the car back though. Damage included: forward band distressed, 1-2 support drum damaged, 2-1 manual band damaged, reaction sun gear damaged, reaction complete carrier broken, input carrier broken, reverse reaction drum and input sun gear damaged....So basically I destroyed my tranny! I will contact them about torque converter tonight or tommorow

 

kinda worried now, just picked up my GXP with 46K, seems to be in very good shape, has brand new Khumos all around, previous owner took care of it, trans fluid is nice and red so it looks like a flush was recent, shifts smooth and no hard shifts at all, only i do notice that when it shifts to 4th at about 50-53 mph and the rpms drop to 1500, theyll jump to 2000 then go right back to 1500, dont feel anything in the trans though when this happens......

 

purchased 08 GXP with 86,515 3/15/11 when it was pretty warm out. now that it's getting kind of chilly here in upper DE for the time being, started to notice problems. after cold start, put in drive, and slightly step on gas, slip occurs. if you let off and ease goes fine, but if i continue to give gas slight shudder occurs. also seems to slip slightly from 1st to 2nd when cold. going to go and see if dealer can do something since it should be under transferrable 5/100 warranty. fluid is kind of brown but know that it really won't fix the problem if i just change fluid and filter, but may do so before taking it in.

 

dont waste your $$ on a flush, take it in and have it fixed under warranty before that expires! I wish mine was under factory so I can have piece of mind....

 

When im driving lets say 60mph on highway And rpms are at around 2k it feels like when they go up they begin to fall down slightly as if I am losing power does that have to do with my tranny?

 

i dropped it off and did nothing to the fluid. it was warmer out yesterday when i took it. it didn't do what i was talking about but i did notice it slip in a higher gear not sure which one it was. i feel it's just a matter of time especially since i was going to take it to the track to see what it has.

 

i don't know what speed it shifts to 4th gear when cruising normally but that's what it sounds like it's doing. i just got mine so not to used to it yet.

 

my trans shifts from 2-3 pretty quick once its in 2nd, within a few seconds..............and the RPMs jump slightly when in 4th sometimes, i thought that was the DOD kicking in, are these trans problems?? Help me, i just bought this car and cant afford a trans right now......its got 46K miles

 

That could be a lot of things. Does it do this all the time? If not, under what circumstances will it do it? When it happens, does is to it once each occurrence or does it oscillate?

This should be covered under warranty. Hopefully, you can get it to do it for the dealer. Of course, as stock rebuild only means that you're likely to experience more problems in the future. I suggest you search this site for more info.

Oh, and I added you to the list.

A factory rebuild or rebuilt unit will still have the same flaws as your stock trans. I suggest you read this thread and search this site, as well as gmls4.com, for info regarding how to prevent these issues.

I'm not sure I understand what you're saying.

DoD can cause a slight RPM surge when going from 4 cylinder mode back into 8 cylinder mode, but NOT when going from 8 cylinders down to 4. Under what driving conditions do you notice the RPM jump that you describe?