eeeny

Hi,

My 2005 c6 makes a clanking/knocking sound when I make a very tight turn whilke moving slowly forward or backwards.

I sounds like it's comng either from the torque tube tunnel or from
transaxel.

The is no wierd sound once the car is moving at speeds above 5mph or so.

Is this noise normal, or is there something wrong.
Has anyone else experience this?

Thanks,

Ian

Zymurgy

Sounds like rear axle chatter. It is not normal, although it is common. There is a TSB on it. Take it to the dealer. Their first action will be to replace the differential fluid and additive. That fixes it for most people. If it returns, then they will replace the differential clutch packs.

meaniam

i have experinced this. but i figured it was suspension pop. i have complained about it twice dealership is unable to recreate. and i have not quite figured on how to make it magically appear at command. so i am S.O.L. it did it so loud one time i almost had it towed in. but i got out and looked couldnt see anything lose and tugged on wheel no movement. it appeared fine and nothing has broken. so it maybe normal. id hate to find out at 65mph on the mountain road. i always drive. i suspect first dealership checked it out with top off and radio blasting ( just joking but this maybe how they missed this)




this maybe the problem as i noticed my rearaxle acting like a locker rearend when backing up and turning at same time. i complained about that 4 times. then switched dealerships and they did the oil change out with additive. havent driven it enough to be sure it is gone but it hasnt been obvious when backing up. but i still hear the popping going forward. and my suspect front suspension or steering as it only noticed at low speeds, and uneven surfaces and low speed turning.

eeeny

Thanks for the info,

Ian

WMark

Had the same noise from my 2002 C5, but only after around 30k miles. Some friends with C5's had the same noise. My dealer (friend's dealers) all said it was "normal."

Haven't heard it in my new (used) 2006 C6, but now that you have mentioned it, I think I'm going to do a little test tomorrow.

barakmd

Disregard, tried different search parameters...

studlee2

Does anyone have the TSB?

andyandy98

tama2112

My 05' just started doing this as well.. What should i tell the dealer when i call to schedule service?

Dave S

TSB # is 07-04-20-002, dated 4-16-2007, document ID 1961528.

PM me a fax # & I'll send to you.

HawaiiC6

Here is the TSB which I found on this site on the rear end chatter. Hope this helps.

You only want the #?

Rear Axle Chatter Shudder on Turns - keywords differential fluid noise oil #PIP3559 - (Sep 22, 2005)
Rear Axle Chatter Shudder on Turns
1999-2006 Chevrolet Corvette

2004-2006 Cadillac XLR

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:
Rear axle chatter or shudder on turns on Chevrolet Corvette and Cadillac XLR.

Recommendation/Instructions:
If this is the first complaint for this condition flush and fill the rear axle with P/N 89021669 (in Canada 89021670) gear lube and 4 ounces of the friction modifier additive P/N 01052358 (in Canada 992694).
If this is a repeat complaint or the condition persists after the flush and fill, replace the right and left rear axle clutch packs following published service procedures.
After clutch pack replacement use 1.6 l (1.69 qt) synthetic axle lubricant GM P/N 12378261 (Canadian P/N 10953455). and 4 ounces of the friction modifier additive P/N 01052358 (in Canada 992694).
Note: 2006 Z06 equipped vehicles require 2.55 l (2.70 qt) synthetic axle lubricant GM P/N 12378261 (Canadian P/N 10953455) and approximately 190 ml (6.4 oz) limited-slip differential lubricant additive GM P/N 1052358 (Canadian P/N 992694).

Note: Export vehicles use 2.01 l (2.12 qt) synthetic axle lubricant GM P/N 12378261 (Canadian P/N 10953455) and approximately 150 ml (5.1 oz) limited-slip differential lubricant additive GM P/N 1052358 (Canadian P/N 992694).

Once the axle fluid has been changed the car must be driven in 8 - 10 SLOW figure eights to work the fluid between the clutch plates.

PAmotorman

make sure ther axle nuts are torqued to 140#

n2f

I had the clunking sound at slow speeds when backing up so when I had the car in for an oil cahnge, the dealership changed out the diff fluid and it hasn't done it since (it's now been about 12,000 miles since this change was made).

But I also had a separate weird metalic popping sound from the back of the car at slow speeds when turning so the next time it was in on a service interval, I had them look at that. Turned out to be an end link on the rear sway bar.

No charge for either of these - parts were repaired/replaced under warranty, the first visit.

Both of these situations did not effect the performance or handling of the car, but they did make for some really weird noises.

User 2623

Clanking or Clunking makes a difference?

If clunking:

So for future reference and those who research the threads before putting it out there here's what I've complied over the issue:
------------------------------------------------------------
Item 1 : rear clunking sound some times very loud when in stop an go traffic, driving at slow speeds. Car lunges forward when changing gears from 1st to 2nd and especially coming on and off throttle. Very rough shifts from 1st to 3rd and noticeable slippage.

Item 2: When backing up and turning the wheels, making a turn grinding sound.

Notes/Actions:
--------------------------
Rear Differential Clunking: Refer to TSB post
Date; 04-16-2007
TSB: #07-04-20-002
Document ID #: 1961528

Subject: Rear Excel Clunk/Chatter Type noise on Turns (Drain/Refill Rear differential Fluid and add specified limited-slip axle additive.

1.Replace rear Differential fluid and add two shots (doses) of sip additive be certain the 4-ounce bottle of friction modifier is shaken thoroughly before it is pumped into the diff. Immediately afterwards do a series of slow Figure-8s to distribute the lube among the diff's clutch plate surfaces. (consider Amsoil as the rear differential fluid Use Amsoils "Severe Gear" 75w-90.)

2. If the noise is still there after a dozen figure-8s, there are possible alternatives causes Please check the following:
......i. Transmission Mounts & u-joint
......ii. the axle nuts are loose
......iii. the rear sway bar connectors are loose
......iv. Clutch packs need replacing


Also refer to this tread DIY – Rear Axle / Differential oil change, with pics – for FAQ - comprehensive post.


3. Possible Transmission Value issue - P0751 - Valve Shift Solenoid Stuck Off. Check the following:
1-24236927 Seal Kit 4.005
1-24238968 Valve 4.265
1-24232240 Body 4.265
10-88861003 Fluid 8.800

Texas Corvette

I had same problem-told service rep about the sound when I made repair appt. and thought that it was the same problem as mentioned in the tsb; when I dropped off the car at the dealer had a copy of the TSB with me. Service rep said we will take care of it. No problem since and no questions asked by the dealer and covered under warranty.

cincyspider

Same problem here till I took it to the dealer and they changed fluids per the TSB....no noises since!!

dpat1

I also had the same problem. Took it to the dealer and they worked the TSB and also found a loose cross member which needed to be tightened and torqued. Has work fine since.

KarlK

I had the chatter and took my vette in twice for the GM fluid change and additive. Chatter returned so I replaced the fluid with Amsoil severe duty differential fluid.

About a year later I started to hear a "popping" noise from the front and rear when going over small bumps, etc. Found two worn sway bar links. Replaced them eventually with Pfadt heavy duty sway bar links.

1. Chatter: Replace rear differential fluid with Amsoil 75-90 Severe Duty
2. Popping: Sway bar links, have them checked front and back. Not just check tightness but play in heim joint where it connects to the bar.
3. Chatter: Rear axle nut loose.

JACK FRISSINA

same problem , clutch pac replaced was the answer.

*FAÇADE*

Here is the most recent GM TSB regarding this condition: