[Stryfe]

About to hit 2000 miles and want to change out my diff fluid.

I've read on here and in the manual that for Camaro's fitted with the LT1, you want 1.2 quarts of differential fluid. It also states to add the fluid additive.

The part number for the fluid is 88900401 and the additive is 88900330.

Now my question is, do I put in the 1.2 quarts of differential fluid AND THEN ADD the full 4 oz bottle of additive to it?

[Max RS]

Add the additive first and follow up with fluid.

[drivingagain]

Buy the oil with the additive already in it from GM. Shake it well and fill differential with 1.2 quarts of fluid or until it comes out of the bottom hole, about the same.

[Eric SS]

The correct P/N is 88862624 and you do not need to add the additive. Just did mine this morning at 1,800 miles and it was very easy. All you need is a 3/8 ratchet as far as tools are concerned. Use the slope on your driveway and ramps so you don't have to put all 4 corners on jackstands if you can't fit under.

I only had about 1L come out and it took about 1.3L so I'm wondering if they are slightly under filled at the factory.

[Gunmetalmissle]

The owners manual was changed to specify fluid plus additive as opposed to just the ls fluid.

[Eric SS]

Originally Posted by Gunmetalmissle

The owners manual was changed to specify fluid plus additive as opposed to just the ls fluid.

There still seems to be some discrepancy. http://www.camaro6.com/forums/showthread.php?t=459727

Since I had no groan, I went with the oil without the extra bottle of friction modifier. A lot of people with the groan have changed the fluid without adding the modifier and had it go away as well.

[Gunmetalmissle]

Originally Posted by Eric SS

There still seems to be some discrepancy. http://www.camaro6.com/forums/showthread.php?t=459727

Since I had no groan, I went with the oil without the extra bottle of friction modifier. A lot of people with the groan have changed the fluid without adding the modifier and had it go away as well.

Bad on GM for making this a guessing game. However, there is no discrepancy in my mind. Based on past GM vehicles the fluid that already has the additive never works well in the long run. Add to that all the diff problems people seem to be having with these cars.

To top it all off my local dealer claimed the computer system told them to use the non-limited slip oil and no additive in my SS. Obviously wrong. The head service manager did additional research and confirmed that the proper fluid is the synthetic oil plus the additional additive.

I'm trying to figure out who makes the lsd. I'm guess Eaton but not sure. On Eatons website they specify GM fluid plus additive OR castrol carbon mod. Carbon mod is the factory fill for the g8 and SS sedan.

Just trying to help someone from wasting their time/money.

[Eric SS]

Originally Posted by Gunmetalmissle

Bad on GM for making this a guessing game. However, there is no discrepancy in my mind. Based on past GM vehicles the fluid that already has the additive never works well in the long run. Add to that all the diff problems people seem to be having with these cars.

To top it all off my local dealer claimed the computer system told them to use the non-limited slip oil and no additive in my SS. Obviously wrong. The head service manager did additional research and confirmed that the proper fluid is the synthetic oil plus the additional additive.

I'm trying to figure out who makes the lsd. I'm guess Eaton but not sure. On Eatons website they specify GM fluid plus additive OR castrol carbon mod. Carbon mod is the factory fill for the g8 and SS sedan.

Just trying to help someone from wasting their time/money.

Any input is good input on this subject! If it starts to groan I'll throw some modifier in it. My guess is Eaton as well but it would be nice to see it confirmed. The gear oil retails for $26/bottle but you can get it for much cheaper if you have a good parts guy at your local dealership. so it's not that big of a deal if I have to change it out again. Cheers!

[oneredry]

Eric SS had it right. I've done exhaustive research, talked with GM engeineers ect. about this subject. Granted the "adding of the modifier is what the owners manual states" but GM (direct from the horses mouth) said by adding the number ending in 24 (already added) is the exact same thing. they did this to cut the confusion (if that makes sense). They are finding out its not the fluid, but more so on how the markings were on the gear set, wearing off not the fluid which is causing the clutch packs to make that growling noise. (hence the early flush). Now they are finding out that it could actually be the mfgr of the diff packs not correct. I just had my carrier replaced and so far so good. Although, once it hits 1500 miles again I am still flushing it.

[somewhatdamaged]

Originally Posted by oneredry

Eric SS had it right. I've done exhaustive research, talked with GM engeineers ect. about this subject. Granted the "adding of the modifier is what the owners manual states" but GM (direct from the horses mouth) said by adding the number ending in 24 (already added) is the exact same thing. they did this to cut the confusion (if that makes sense). They are finding out its not the fluid, but more so on how the markings were on the gear set, wearing off not the fluid which is causing the clutch packs to make that growling noise. (hence the early flush). Now they are finding out that it could actually be the mfgr of the diff packs not correct. I just had my carrier replaced and so far so good. Although, once it hits 1500 miles again I am still flushing it.

Thanks for this information - it's the most through explanation of the rear end groan issue that so many have been experiencing.

[evanescent03]

Originally Posted by Eric SS

The correct P/N is 88862624 and you do not need to add the additive. Just did mine this morning at 1,800 miles and it was very easy. All you need is a 3/8 ratchet as far as tools are concerned. Use the slope on your driveway and ramps so you don't have to put all 4 corners on jackstands if you can't fit under.

I only had about 1L come out and it took about 1.3L so I'm wondering if they are slightly under filled at the factory.

did you use a transfer pump or just some creative pouring to refill? thanks!

[Eric SS]

Originally Posted by evanescent03

did you use a transfer pump or just some creative pouring to refill? thanks!

I used a pump that you can buy at Walmart that screws into the top of the bottle.

[Tridon]

I know you all are talking about this relating to the SS, but is it also necessary to flush the differential in a V6 manual at 2k?

[Blade]

Does the car need to be level to drain this myself? I can put mine on ramps, I don’t have a driveway long enough where I keep it leveled since I live in a townhome.