synthetic oils

d745

My usggest is that you read your owner's guide. It will tell you what specifications the oils should meet. Be careful of some of the Amsoil engine oils. Some are API certified and some are not. Your owner's guide is going to specifiy that the engine oil be API certified.

Here are recommendations for the other fluids from the GM manual -

Automatic Transmission - DEXRON III Automatic Transmission Fluid

Front Axle - SAE 80W-90 Lubricant (GM P-N 1052271, Canadian P-N 10950849 or equivalent).

Front and Rear Axle (5 Spd.) - SAE 75W-90 Synthetic Axle lubricant (GM Part No. 12378261, Canadian Part No. 10953455) or equivalent meeting GM specification 9986115

Rear Axle (With QS4 Axle only) - SAE 75W-90 Synthetic Axle Lubricant (GM Part No. 12378557, Canadian Part No. 88901362) or equivalent.

Transfer Case - NVG 149-NP (One Speed Automatic) - DEXRON III Automatic Transmission Fluid (GM P-N 12346143, Canada P-N 10952622) or equivalent.

Transfer Case - NVG 236-246-NP8 (Two Speed Automatic) - Auto-Trac II Fluid (GM Part No. 12378508, Canada Part No. 10953626) or equivalent.

Transfer Case - NVG 261-NP2 (Two Speed Manual) - DEXRON III Automatic Transmission Fluid (GM P-N 12346143, Canada P-N 10952622) or equivalent.

Transfer Case - NVG 263-NP1 (Selectable) - DEXRON III Automatic Transmission Fluid (GM P-N 12346143, Canada P-N 10952622) or equivalent.

Using synthetic fluids is fine, just make sure they reflect the appropriate GM specifications.

Ed