Rear Diff Groan Gone

KenH. · 01-15-2018, 12:33 PM

This latest installment in a long line off issues that practically keeps a bay reserved at the dealership for my car includes getting a new drivers side rear axle.

Under moderate acceleration it appears either all the bolts sheared from the diff flange to axle or they were loose and damaged and I couldn't tell as they all slowly broke off, because they were all gone and my axle was sitting on my exhaust pipe.

Maybe I couldn't tell because of the diff groan when turning, or maybe the diff groan was because of the axle situation because since they have replaced the axle my diff groan is gone.

I figured this particular experience was worth sharing.

KenH. · 01-15-2018, 03:58 PM

I have a coworker with a 17 2ss and his diff groan is unbearable...he plans to sell the car. He actually got a settlement from GM over it after they said they wouldn't fix it. It literally sounds like an old piece of crap groaning and creaking as he pulls out of the parking lot at work. He's going to take his to the dealer and have the axles those bolts checked.

Emoto · 01-15-2018, 04:17 PM

Where are these bolts, exactly? Do I need to pull a wheel to see them?

KenH. · 01-19-2018, 03:22 PM

You don't need to pull a wheel to see them you can see them by just getting down and looking under the car at where the axles meet the differential. You will see the flange and all the bolts connecting them together on each side.

I still have zero groan noise since replacement.

You would think if this really is the source of the problem GM would have figured it out by now and engineered a fix. I would not expect my car to have enough power to snap those bolts without there being a problem like some form of misalignment causing added stress.

I want to enjoy my good fortune, but I worry it's gonna come back.

ChevyRules · 01-19-2018, 03:47 PM

This is interesting considering the fluid change would get rid of the noise. So I am definitely curious on how these bolts would cause the issue, but go away with a fluid change.

But this is definitely a easier case to go to the NHTSA to get an investigation going to either force a recall or get GM to take this seriously. I hope the dealers are reporting it to GM so they could investigate themselves.

Though my car so far has not developed the rear diff groan yet.

ChevyRules · 01-19-2018, 04:21 PM

Quote:

Originally Posted by cooper1965

GM has requested all of our replacements be sent in. They are looking at it. I should have added, the last shaft that the bolts were not "visibly" loose or damaged, had threads on the bolts damaged after removal of the shaft.
As far as the fluid flush curing the issue, I'm confident that will only last temporarily.

I am too as many have reported having the noise come back. I am just curious on how the change would cause it to go away at least for a short while.

KingLT1 · 01-20-2018, 07:11 AM

my axel bolts were all torqued and marked with a blue marker. The marks are all still aligned so the bolt's are tight and I still get some groan with the first few sharp turns even after 3 diff flushes. It does go away pretty fast and then is quiet and smooth. Curious to see how bad it is when I get it out of storage this spring.

motorhead · 01-20-2018, 08:28 AM

This just nuts. My in law's came back. He's talking about trading his for a Vette. The differential was invented in 1827. Wouldn't you think it should be pretty damn problem free by now?

01-15-2018, 12:33 PM	#1
KenH. Drives: 2016 2SS M6 NPP MRC Join Date: Jul 2016 Location: Graham, NC Posts: 190	Rear Diff Groan Gone This latest installment in a long line off issues that practically keeps a bay reserved at the dealership for my car includes getting a new drivers side rear axle. Under moderate acceleration it appears either all the bolts sheared from the diff flange to axle or they were loose and damaged and I couldn't tell as they all slowly broke off, because they were all gone and my axle was sitting on my exhaust pipe. Maybe I couldn't tell because of the diff groan when turning, or maybe the diff groan was because of the axle situation because since they have replaced the axle my diff groan is gone. I figured this particular experience was worth sharing.

01-15-2018, 04:17 PM	#3
Emoto Sure, why not? Drives: 2016 Camaro 2SS, Jeep JKU Rubicon Join Date: Mar 2015 Location: SE Mass Posts: 1,538	Where are these bolts, exactly? Do I need to pull a wheel to see them? __________________ This is that witty and clever statement that makes you chuckle.

01-19-2018, 03:47 PM	#5
ChevyRules Drives: 2021 Tesla Model 3 LR Join Date: May 2016 Location: USA Posts: 964	This is interesting considering the fluid change would get rid of the noise. So I am definitely curious on how these bolts would cause the issue, but go away with a fluid change. But this is definitely a easier case to go to the NHTSA to get an investigation going to either force a recall or get GM to take this seriously. I hope the dealers are reporting it to GM so they could investigate themselves. Though my car so far has not developed the rear diff groan yet. Last edited by ChevyRules; 01-19-2018 at 04:22 PM.

01-20-2018, 07:11 AM	#7
KingLT1 Drives: 2016 1SS NFG A8 Join Date: Aug 2017 Location: 46804 Posts: 6,800	my axel bolts were all torqued and marked with a blue marker. The marks are all still aligned so the bolt's are tight and I still get some groan with the first few sharp turns even after 3 diff flushes. It does go away pretty fast and then is quiet and smooth. Curious to see how bad it is when I get it out of storage this spring. __________________ 2016 NFG 1SS A8 Options-2SS Leather/NPP Perf. mods-Whipple 2.9/Fuel System/Flex Fuel/103mm TB/Rotofab Big Gulp/Cat Deletes/Corsa NPP Per. times- 10.5 @ 137 w/ 1.8 60ft Full weight on 20's 1200DA

01-15-2018, 03:58 PM	#2
KenH. Drives: 2016 2SS M6 NPP MRC Join Date: Jul 2016 Location: Graham, NC Posts: 190	I have a coworker with a 17 2ss and his diff groan is unbearable...he plans to sell the car. He actually got a settlement from GM over it after they said they wouldn't fix it. It literally sounds like an old piece of crap groaning and creaking as he pulls out of the parking lot at work. He's going to take his to the dealer and have the axles those bolts checked.

01-19-2018, 03:22 PM	#4
KenH. Drives: 2016 2SS M6 NPP MRC Join Date: Jul 2016 Location: Graham, NC Posts: 190	You don't need to pull a wheel to see them you can see them by just getting down and looking under the car at where the axles meet the differential. You will see the flange and all the bolts connecting them together on each side. I still have zero groan noise since replacement. You would think if this really is the source of the problem GM would have figured it out by now and engineered a fix. I would not expect my car to have enough power to snap those bolts without there being a problem like some form of misalignment causing added stress. I want to enjoy my good fortune, but I worry it's gonna come back.

01-20-2018, 08:28 AM	#8
motorhead Drives: Love the one you're with Join Date: Sep 2009 Location: Downtown Charlie Brown Posts: 11,850	This just nuts. My in law's came back. He's talking about trading his for a Vette. The differential was invented in 1827. Wouldn't you think it should be pretty damn problem free by now?

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