CHEVROLET CORVETTE 2005 - Manual (Page 303)

Rear Axle
When to Check Lubricant
It is not necessary to regularly check rear axle fluid
unless you suspect there is a leak or you hear an
unusual noise. A fluid loss could indicate a problem.
Have it inspected and repaired.
How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.
If the level is below the bottom of the filler plug hole, you
will need to add some lubricant. Add enough lubricant to
raise the level to the bottom of the filler plug hole.
What to Use
To add lubricant when the level is low, use
SAE 75W–90 Synthetic Axle Lubricant (GM Part
No. U.S. 12378261, in Canada 10953455) meeting
GM Specification 9986115. To completely refill after
draining, add 4 ounces (118 ml) of Limited-Slip
Axle Lubricant Additive (GM Part No. U.S. 1052358, in
Canada 992694). Then fill to the bottom of the filler
plug hole with the Synthetic Gear Lubricant.
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