Ok
Last night after taking the father in-law out for a quick spin to compare the Z06 power to my Mustang Gt, I started getting a loud “clunk” coming from the transmission. The car still shifts easy into all gears, but if you “pop” the throttle either on, or off power there is a loud clunk. I can also hold in the clutch and move the shifter between gears to replicate the sound. Both transmission and rear differential fluids have been recently changed. This issue seems to be different than the half shaft retaining nut torque problem, since my car has no issues on a turn, just straight accelerating or decelerating

Thanks for any help

 

bump

 

I've noticed this issue too.

 

Any help would be appreciated.
Does this sound like a transmission, rear differentail or other problem?

Thanks
Steve

 

I also noticed this...hoping it's nothing major since I haven't had any problems shifting etc. Anyone have any ideas???

 

I think it's a bushing or trans-mount issue. When the trans-mount went bad in my Trans Am there was a similar clunk.

 

Mine is starting to do this as well...

I'm thinking Tranny mount as well.

-Adam

Corvettes of Dallas

 

Ok,

I had a local mechanic put the car up on a lift and he noticed that there seemed to be a significant amount of "play" (fore and back not side to side) at the rear wheels with the car in gear. Is there a spec on how much slack there should be at the rear wheels while in gear? He could create the noise buy quickly rolling the wheel forward or rear.

 

I was planning on bringing this issue up because I figured alot of people might have this problem and not even know it.
If what I am understanding everyone describing is what I called "drive line slop" I just couldn't describe it any other way.
My car as well as 2 others here in the recent past had this same issue. While trying to figure out another problem I tightened my Axle Nuts. They are a 34mm if I'm not mistaken.(car on the ground) I popped the center cap off, took an impact and Loosened them a bit and then drove them home again good and tight. (150lbs is the torque spec I believe) But I just let the impact lock them down and backed it up with a breaker bar.
Well the prob I was hoping to solve was still there (tranny) but low and behold my "drive line slop" was gone and I mean GONE!! also GONE was my car wanting to push and pull me from one lane to the other on the highway when when changing lanes. Like the car would be bouncing around in the ruts or something during lane change.
It wasn't 2 weeks later a friends car was having the noise the OP described, we took a ride I told him "That's Axel Nuts!!!" we tightened them up in the parking lot of the closest Auto Zone and Noise gone!!!

Hope this helps.

 

Your gears will have some play back and forth, if it's excessive it will be accompanied with gear noise (howling) and you'll know when that happens.

 

Thanks for the replys

Axel nuts were checked and tightened and no excess noise in the transmission??

Steve

 

Interesting... Maybe that's the issue. I also get a little hop-n-pull when I hit road brail on the freeway while changing lanes.

 

OOps,

My last comment came out wrong. I meant to say that I have had the axel nuts checked and that did not cure the problem. When the car was up on the lift the noise seemed to be comming from the front of the transmission or back of the torque tube.

Steve

 

i have the same problem and i came across this thread by member jbauch357 in the diy section, not to steal his thunder but it is a very good thread, i still have to try it, but if you look under the tech section there is a diy thread, it has pics of how to do it also




Popping rear axle fix

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Here are all of the tools that you will need: 33mm deep well 6-point socket (I purchased replacement spindle buts that had 34mm heads, so double check this before sitting down to do the job), 19mm socket, torque wrench, wheel lock key, some penetrating fluid (I prefer "PB Blaster" but didn't have any handy when I did this) and some synthetic grease (not pictured).
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Pull off the center cap for your wheels and break loose the lug nuts and output shaft spindle nut. The spindle nut could be pretty tight so don't be surprised if it takes a bit of elbow grease to get it to break loose.
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Jack up the rear end, support the car, spin the lug nuts off, and remove the rear wheels, you will now be looking at this.
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Now you don't have to worry about hitting your wheel with the torque wrench or busting your knuckes open on the wheel. Remove the spindle nut the rest of the way and take a good look at what is behind it.

Now we can see the front side of the splines that mate the output shaft and the hub assembly. Go ahead and give a little squirt of the penetrating fluid into these ridges, but not too much cause this isn't the important part. If you push in (towards the transmission) on the middle of the output shaft it should slide in to the hub. If it's rusted in place a light tap with brass hammer or mallet should break it loose so you can now move it by hand.
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Now while pushing in look behind the hub assembly and look at where the drive shaft actually goes into the hub. If you look carefully you can see the splines entering the hub, and the mating surface of where the drive shaft buts against the hub. Give this area a nice layer of synthetic grease, both on the splines and the flat portion where output shaft meets hub (I used penetrating fluid the first couple times around but the problem kept coming back, once I used grease it stayed gone).
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Work the spindle back and fourth in the hub a few times to make sure that the penetrating fluid has completely covered the splines and all contact areas have at least a thin layer of grease on them.

Spin the spindle nut back on until snug, put your wheel back on and snug the lug nuts down. Drop back to the ground and torque the spindle nut to 118 ft/lbs and the lug nuts to 100 ft/lbs (make sure to torque in a star pattern so you get even torque).

Now go for a test drive and listen to the beautiful silence coming from the rear end. After driving a few miles I like to double check torque on the spindle nut, but I don't know how necessary that really is.

Hope this helps!!!

 

woops, i just read your post that you had the axel nuts checked, sorry

 

I

I had the clicking and popping noise coming from rear passenger side. I followed this post to the letter and was so happy that it fixed my issue. The splines was seized in the hub. Rust disolver and a couple gentle taps and it was freed up. Dried it up and sprayed splines with white lithium grease. I've ordered two new axle nuts but was curious to try before they arrive. I torqued to 118 ft. Lbs as per GM tech. I see some guys are torquing to 160 ft. Lbs. Tech told me 118 ft. Lbs or 160 NM
Anyway Yellow valve springs have been replaced. New rubber and really love my 2002 Z06 ! Thanks. Love this forum.

 

Closed and moved to C5 Tech.