Rear diff low fluid
Thread Starter
Instructor
Joined: Aug 2008
Posts: 180
Likes: 29
From: PA
Rear diff low fluid
So I've been reading on here about rear diff being low on fluid. Car has 300 miles, I decided to check it and yup almost full quart low with car level.
Car was built 02/2016.
Car was built 02/2016.
Race Director
Joined: Jul 2007
Posts: 10,961
Likes: 2,643
From: Texas Hill Country
Drifting
Joined: Oct 2005
Posts: 1,354
Likes: 717
From: Terrell North Carolina
Don't feel bad, my 2016 Z, built same month as yours was a quart low as well. GM has had many problems with diff not filled correctly, there are many post on the forum about the problem.
Thread Starter
Instructor
Joined: Aug 2008
Posts: 180
Likes: 29
From: PA
Thread Starter
Instructor
Joined: Aug 2008
Posts: 180
Likes: 29
From: PA
A better idea would be to just have them dump the fluid and refill. They will most likely charge for that but it's money well invested to get all the brake-in metal out of there...
Race Director
Joined: Oct 2008
Posts: 16,671
Likes: 7,738
From: NJ
Mine was maybe pint low.
My buddies? Full quart. Checked right after mine maybe 200 miles on his. I had around 400.
unreal.
this forum was why I checked glad I saw it (earlier thread was about a month ago when we had them in air).
My buddies? Full quart. Checked right after mine maybe 200 miles on his. I had around 400.
unreal.
this forum was why I checked glad I saw it (earlier thread was about a month ago when we had them in air).
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Burning Brakes
Joined: Nov 2016
Posts: 774
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My 05 GTO back then was down a 1/2 quart brand new. Found from info back then forums.
Royal purple got rid of a whine it had at 50 mph.
It was in the news that the same assembly worker was transferred to Kentucky where he shorted many diff's till he was arrested!
Royal purple got rid of a whine it had at 50 mph.
It was in the news that the same assembly worker was transferred to Kentucky where he shorted many diff's till he was arrested!
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I recall when I changed the fluid in the rear diff of my last C6 Z, I would fill it until it began to weep out of the fill hole. Then you needed to drive it a short distance or rotate the rear wheels and then top off the fluid. It needed quite a bit more after the fluid circulated. I know the new diffs are filled by the suppliers and then installed in BG. I wonder if this accounts for all the pumpkins low on fluid.
Drifting
Joined: Oct 2014
Posts: 1,673
Likes: 199
My recommendation is that while they are doing the 500 miles oil change to also drain and refill the differential. There is no extra labor since the car is already on the rack and this can be done in parallel with oil change. You just pay for fluid which is around $100. The differential does get very hot during break in. It's a good investment to clear the differential from break in fluid and any possible tiny metal shavings (if any). It's very important to replace the fluid after the first track day as recommended in the manual.
Drifting
Joined: Oct 2014
Posts: 1,673
Likes: 199
This is an electronic rear differential and uses very specific fluid and it's not cheap. I would only use OEM fluid.
Le Mans Master
Joined: May 2000
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From: Redmond WA
Instructor
Joined: Aug 2011
Posts: 119
Likes: 28
From: PA
Knowing that this is a common issue shouldn't the dealers check this prior to delivery to the customer? I am sure many of the larger dealers have heard about this by now.
Melting Slicks
Joined: Feb 2004
Posts: 3,131
Likes: 148
From: Sugar Land TX
Or better yet why doesn't GM check fluid levels before they even leave Bowling Green. This is a problem us owners should not have to be dealing with.
The Consigliere
Joined: May 2006
Posts: 23,003
Likes: 6,045
From: 2023 Z06 & 2010 ZR1
This. The fact customers are still having to deal with improperly filled rear diffs and A8 trannies with problems at this stage of the model run is simply inexcusable.
Drifting
Joined: Jun 2015
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Likes: 554
Thread Starter
Instructor
Joined: Aug 2008
Posts: 180
Likes: 29
From: PA