Amsoil severe gear 75-90
- Thread starter 99TA
- Start date
- Status
What was the previous maintenance history?
How many miles on the vehicle?
How many miles on the vehicle?
It may just be a viscosity issue. Professionally I would have recommended the Amsoil 75W-110 or 75W-140, for a vehicle such as yours with 100K+ miles.
I wish I could find the viscosity for the Rotella. I didn't see it on the web. Rotella
The Amsoil SVG = Kinematic Viscosity @ 100°C, cSt (ASTM D-445) 16.4. Maybe Rotella is at the high end of spec. range....
I think Pablo is probably right about recommending SVT over SVG for your application. I don't know much about your differential gears. Is it a high offset pinion gear? Maybe the Rotella (mineral?) was able to travel the ring and the pinion better under light loads. Anything's possible, but at least you know you can go back to Rotella if you want. It seems to work.
Absolutely as much as you can....enough to drain and refill?
Almost all diff fluids have sulfur EP additives. I'm not sure the point of your link - is your diff a limited slip?
I maintain that your diff has some wear, the Rotella probably is a bit thicker than the Amsoil 75W-90 and merely masked the whine that is only audible at certain speeds (but still there). Either use a thicker Amsoil 75W-140 or switch back to Rotella. Eventually you will need a new differential - or most likely your pinion bearings will need replacing.
- Status