My searches about this differential seem to produce more confusion than good info, on Google. I bought an immaculate dark green metallic 2001 Silverado 2500 HD with the 8.1L big block. I've never been a truck guy but this thing just puts a big smile on my face when I drive it. The old fella who owned it most of its life took exceptional care but it doesn't look like a diff cover has been off it so I'd like to service them. GM specs a 75w90 synthetic for the rear only, regular 80w90 in the front.
My main questions are, shouldn't be an issue to use syn 75w90 in the front and rear? Did GM use a limited-slip in any of these diffs? Transfer case fluid, specs DEX3. In my experience, this is a PITA to find nowadays. Can I run Maxlife or something similar?
2001 is the first year GM used the 11.5" AAM rear. Does anyone know if this came with a Gov Lock? I'm hoping it has a limited slip and not a Gov Lock, it certainly behaves like a limited slip diff. The truck is a tire roaster and any which way you romp on it, it lights up both tires and never gives you any of the chatterings soon after if you make a turn and never any indication of a tire spinning sooner and it engaging. I did not like the govlocks in all my prior 10 bolt Yukon/Suburban/Tahoe.
My main questions are, shouldn't be an issue to use syn 75w90 in the front and rear? Did GM use a limited-slip in any of these diffs? Transfer case fluid, specs DEX3. In my experience, this is a PITA to find nowadays. Can I run Maxlife or something similar?
2001 is the first year GM used the 11.5" AAM rear. Does anyone know if this came with a Gov Lock? I'm hoping it has a limited slip and not a Gov Lock, it certainly behaves like a limited slip diff. The truck is a tire roaster and any which way you romp on it, it lights up both tires and never gives you any of the chatterings soon after if you make a turn and never any indication of a tire spinning sooner and it engaging. I did not like the govlocks in all my prior 10 bolt Yukon/Suburban/Tahoe.