Axles already use SAE 75W-90 Synthetic Axle Lubricant. Tcase uses Dexron III, synthetic might be ok, but the auto uses the new Dexron IV, and it is a lot better than Dexron III.
Can't say if synthetic would be better in the case or not.
Just remember if changing the fluid in the Tcase to make sure it is above the fill hole.
You fill to the fill hole, replace the plug, then remove the speed sensor and add another specified amount. Should be a supplement in your owner's manual, in regard to the Tcase fluid fill procedure.
__________________
Black Sheep Hummer Squadron
(ME TOO)
|