ZL1 Rear end noise
 

I have a 2012 ZL1. The rear end makes this weird humming noise, similar to the sound when your power steering is low, coming from the rear when the wheels are cranked in either reverse or forward. Any help would be great!!!

Same here when she is cold. Once heated up it goes away! 2013 ZL1

I had the same issue. I found the TSB that relates to the issue that the SS has and the dealership honored the work. They replaced the fluid in the rear diff and also changed out the seals (per the TSB).

Since then, I haven't had the sound reappear. I think GM should look at extending the TSB to officially support the ZL1 as well.

theres a private bulletin for the zl1's. Calls to flush the fluid about 3 times and in between those drive it so many miles doing so many figure 8's and a lot of nonsense, all in all majority of the time they are replacing the whole rear end, and when you get it supose to take apart the cover and brake clean inside to get the paint off. The paint they used inside on the gear in the differential to set it, isn't breaking down like its supose to contaminating the lsd.

Do you have the tsb# ??? :thanks:

Im interesyed in thos also. I also notice some sort of loud winning noise espesially in 4yh or 5th gear. Dont recall as im giving it gas.

Just change the fluid, it will go away! takes 20 mins to do. you have to get the diff fluid with ls additive already in it.

May not be related to the fluid issue. Could be improper lash setup in the rear. Changing fluid will not help this problem.

When changing the fluid, how do you flush the old fluid out of the lines and cooler going up to the front?

I had this issue, dealer changed out the fluid and the problem went away.

I just drained at the diff, and filled at the upper plug, noise stopped. If you feel draining at the diff is not good enough and want to get the lines and cooler drained, take it to the dealer. Im sure they use some sort of positive feed pump, but i dont think thats needed.

Draining the lines and cooler would have no effect on the noise. The cooler is running transmission fluid and doesn't mix with the rear diff fluid.

Thanks guys. Sounds like my dealership is changing my fluid!!!

Correct me if I'm wrong, but if there is a feed and return line going from the diff to the front of the car and ran thru a heat exchanger, than there will be old gear fluid in those lines and hx unless flushed.

My fluid was changed by the dealership, and when i turn left or right
at about 5mph i hear a whine or humm.

Ok :biggrin:

From Chevy's site:

The differential cooler is a truly unique design. This innovative system pumps overcooled transmission fluid to a heat exchanger inside the housing, removing excess heat from the differential fluid

I had the same issue, back to the dealer twice, first time the backlash was off, replace ring and pinion, noise went away but came back. Next time they flushed the rearend very good. They think some of the left over lashing compund was causing the whine. It has been quiet ever since and that was about 10,000 miles ago.

Wait a minute... I'm a little confused on that. So the differential fluid is not getting pumped to the front of the car?

Correct...its trans fluid that goes back to the rear diff and picks up some heat off the center section and housing

No. ATF is the meduim used for cooling. Otherwise the system would take more than around 2 qts of fluid to do a rear differential fluid service. I also wonder how well gear oil would circulate, especially compared to a thinner trans fluid.

http://www.camaro5.com/forums/showpo...3&postcount=45 :cool:

My 2013 ZL1 is in the shop now. They drained and flushed the differential 3 times but the noise is still there. I was told they're contacting Detroit to see what the next step is. They've had it for 3 days now. I really miss my ride.

Make sure that your ZL1 was driven for 20 miles between each differential fluid change. My dealer doesn't take my ride off the lot unless I'm aboard, so I put the 60 miles on it and the problem cleared.

Cheers - :nod: Major Boyd

Does it happen while at a cruising speed as well?

My 2013 was doing it on turns and it was noticeable at cursing speeds. When I acc/dec it would go away but while maintaining a speed I could hear it.

Took it to the dealer and they rebuilt the rear end. I've heard of others getting a new rear end for the same issue.

I had mine changed within 30 days of owning. (Tulsa, America) It did work, but 60K miles later it is back. Now they are saying that they want me to pay 600.00. Ha the dealer and GM can kiss my ass. Put the old shit back in and I will go Buy a Ford!!!! Divorces are really very easy these days...

Change your fluid yourself. $40

600 to change the rear diff fluid ? they did mine and it was like 150 canadian

Just starting to research this issue. Installed the ZL1 diff in my 13 SS. Having the same noises. Other than annoyance, is anything being "hurt" by it. I assumed it was just the clutches breaking in. Running Royal Purple FWIW.

I dont think the little noise is really as much of a big deal as everyone made it out to be in the beginning to be honest. Mine did it new, they changed the fluid out and it quieted down a bit. Its still there a little but ive put 20k mi since then and it really is only noticeable when cold. You dont see many "My rear end is shot, blown out, dead, broke etc" threads popping up and plenty of people stil have the noise so I wouldnt worry about it. Beside with some proper exhaust you cant hear it anyway lol.

Well I put about 500 miles on after the installation of the Diff, axles, and driveshaft. Royal Purple fluid, dumped it, filled it again. I've run nearly 5k miles on this fill and still when cold I get the moan. That is what started me researching this phenomena and seeing all the posts and TSB. I wondered if it was the Royal Purple but folks seem to have it on factory fluid as well. If it isn't "hurting" anything then the noise doesn't really bother me. To add to this I am running solid subframe bushings so I am apt to hear a little more than others might anyway.

I had the exact same kind of sound and at 26,000 miles GM gave me a new diff... That one repair paid for the cost of my GMPP warranty... Only problem was it took ten days to get a diff from Detroit out here to Colorado Springs.

use the GM fluid and see if the sound goes away.

What is the GM fluid for the diff ?

WOW $600.00 to change the rear differential fluid, that is unbelievable! That is easier to do than changing the oil, like Bryan stated change it yourself.

Talk about thread from the dead. TSB PIP-5097

http://www.camaro5.com/forums/showth...light=PIP-5097

AC Delco Part Number 88862624 75w-90

Hello,

Rear end differential "noise" on deceleration. This happens when I let off the gas and are coasting. It's pretty faint, but once you notice it you can ear.

ZL1 Conv. 2014 - 40.000kms
automatic gearbox replaced at 30.000kms

How to solve? Any feedbacks? Thank you.

Ascertain proper fluid (AC Delco 10-4034, GM#88862624) is present and appropriately filled. Why was the transmission replaced at 30k kms?

Replacement of fluid planned next Tuesday with 2.1 litters of :
https://uploads.tapatalk-cdn.com/202...eb4ce4dda6.jpg

Transmission replaced by previous owner.
It seem he was adept of runs and burns

If he screwed up the transmission, I'm just hoping he didn't do the same to the differential.