After Diff Rebuild When to change fluid.

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Jun 11, 2022 | 06:09 PM

cagotzmann

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Melting Slicks

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After Diff Rebuild When to change fluid.

So after a diff complete rebuild / New gears / Clutch packs / Bearings etc.

When should the diff fluid be changed. ?

Jun 11, 2022 | 06:12 PM

69ttop502

Le Mans Master

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From: Watkinsville, GA and Glen Cove, NY

Mike Dyer told me to do it at 500 miles.

Jun 11, 2022 | 11:52 PM

gkull

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From: Reno Nevada

2024 C3 of the Year Finalist- Modified

What did you put in it for gear oil? Gary R would be my guide, but I run my new ones for a couple of months before a change. 500 seems low, but I spray mine out with brake clean/ carb cleaner to get all the yellow out before buttoning up.

Jun 12, 2022 | 01:35 AM

cagotzmann

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Melting Slicks

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Quote:

Originally Posted by gkull

What did you put in it for gear oil? Gary R would be my guide, ut I run my new ones for a couple of months before a change. 500 seems low, but I spray mine out with brake clean/ carb cleaner to get all the yellow out before buttoning up.

Chev / GM Diff fluids. Same fluid I have been using in the original factory diff for the past 220k km. Never found a reason to use something else.

Jun 12, 2022 | 02:43 AM

76strokervette

Burning Brakes

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From: Willoughby Ohio

500 miles was the factory break in spec for many years. If gears are rem polished that can change things.

Jun 12, 2022 | 07:54 AM

60 SHARK

Melting Slicks

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From: CLEVELAND STUCK IN OHIO

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I just got mine back from Gary R , Awesom work, by the way, His recommendation is 500miles then change fluid. I’m useing Lucas oil plus’s two (2) bottles of GM additive. .

Jun 12, 2022 | 10:32 AM

Arg0413

Drifting

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From: Baton Rouge Louisiana

500 miles is fine, but you also need to go through the proper break in procedure with correct heat cycles to ensure the gears break in correctly:

No hard pulls for first 500 miles, drive her gently.
First drive should be 15 minutes with varying speeds under 55MPH. Park and allow diff to cool before next drive.
Second drive should be 20 minutes with varying speeds and cruising around 65 MPH.
third drive i like to do an highway or interstate run for 10 minutes then stop and go around town for another 20.
I change my diff oil after this - dont freak out at all the glitter lol
I then change my diff oil again after the 500 - 500 mile mark. Gear oil is cheap insurance!

Jun 12, 2022 | 11:32 AM

gkull

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From: Reno Nevada

2024 C3 of the Year Finalist- Modified

for higher numeric ratios which get hotter and lapping cars. Plus posi lube. I usually put in one and run it for awhile and if you still get popping and a second one.