[blackZ34]

Like the title says, I'm hearing a big noise when I put the tranny in gears. It seems to make it louder when passing from Park to Reverse. At first I was thinking a bad motor mount but I changed the passenger side one (bottom) and looked at the others ones and they all seem fine.

Now I'm thinking this noise is coming from the tranny. Can it be the differential? (it reminds me the noise of a RWD with a bad driveshaft joint)

Another problem since this noise appears is that the tranny is acting really weird when cold. It seems to slip but the shift are still hard. Let's say I barely give throttle, in 1st , it seems to shift in 2nd, then downshift in first... When the car is hot everything seems fine.

 

[blackZ34]

Update: the tranny slipping I was talking about seems more like an OD problem. It only happens when in OD, or maybe it's the torque locking and unlocking??

And still have that horrible "CLUNK !" when I change gears, but more when passing from PARK to REVERSE... (maybe the diff ?)

 

[BIG JEFF]

Guillame,


I would look closely at the lower ENGINE mount. They can collapse internally and cause this symptom. Additionally, upper engine mounts can cause this as well.




BIG JEFF

 

[blackZ34]

Guillame,


I would look closely at the lower ENGINE mount. They can collapse internally and cause this symptom. Additionally, upper engine mounts can cause this as well.




BIG JEFF

I put a brand new one lower engine mount (the one I had was new too but it has a 1 year warranty so I changed it too see) and I also inspected the upper one and I turned the bushig 1/4 turn in it to make them a little bit stiffer when engine rocks.

Nothing of the above help

It really looks like there is something loose in the tranny before it engage into gears.

 

[blackZ34]

UPDATE:
Tranny finally threw a code0742(torque converter clutch circuit stuck on)

Any ideas of what the problem could be?
Or is it just a bad TCC solenoid ?

 

[blackZ34]

Someone?

 

[UrbelT]

Possible TOGs hitting?

Hmm, not sure but a similar loud thump when shifting into reverse or out sometimes. I think my TOGs might be hitting somewhere. I have not flipped my swaybar because it looks like it is not hitting it, but I think I will just to make sure.

-UrbelT

 

[BIG JEFF]

Howdy,


Well, I think the p0742 code certainly lends credibility to the trans problem theory. The most common cause for this is the converter, although solenoids or valve body can also cause this issue. The screwball "slipping" symptoms sound like a valve body issue. The valve body may also be causing the p0742. Unfortunately the p0742 code usually k.o.'s the converter and will stretch the drive chain in the process. I recommend a reputable trans professional in your area.


BIG JEFF

 

[Drewfus2101]

This is probably not your problem, but I had a similar problem. It turned out tha my mufflers were banging. Only happend when shifting into reverse.

 

[blackZ34]

Definatly not a headers/exhaust hitting problem.

My car is now stored for winter so I have in mind to get a couple of things this winter to be installed for the next season.

I want:

-new TC
-3.69 gears
-shift kit
-improved boost valve and sleeve kit
-LSD (already ordered )
-new valve body
-probably almost every solenoid in the tranny ( the TC one for sure!!)

I don't feel like removing the tranny 2-3 times just because what I changed wasn't the problem...

Is there something in that list that need special tools or skills to be replaced?

 

[FreemenGMTech]

Big Clunk... problems shifting from 1-2nd gears... does the dash seem to "shudder" about 1-2" if so you are looking at a pressure control solenoid issue, if not and the transmission is a 99-00 vintage trans you could be experiencing input shaft bearing failure [usually accompanied with a whine when idle in gear foot on brake] if it is late 00-early 02 you should look into a failing input reaction carrier needle bearing...

thing i have been dealing with at the dealer over the years.