hey guys! i'm about to change my differential oil with streering fluid too.
what brand(thinking royal purple) and weight do Yukon denali use?
thanks

 

LSD?

Should be 75-90 Full SYN

 

yeah 75-90 both front and rear?
thanks

 

front is 80-90

 

Royal Purple in Eddie Smith's NHRA race cars are faster than Mobil 1 fills (engine & drivetrain). Thats good enuf for me. Max Gear 75w90 in my diffs. There is less drag w/synthetic in front, I need more brake pedal to stop...

 

I'm using GM 75-90 synthetic front and rear...the truck originally came with 80-90 dino oil in the front, but I read an old TSB in reference to transfer case issues in colder climates. Seems the autotrak can't overcome the thick viscosity of the dino gear oil and takes a poop (as per the TSB)

 

I was thinking about Schaeffer's synthetic gear oil. I have hear good things about schaeffers! has anyone used it?...... compare to royal purple, how is it?

 

Can you elaberate on this? why would you put steering fluid in the diff?

 

i'm NOT gonna put steering fluid into diff. why would I?
I said I'm going to change or add steering fluid into steering. Not to differential!

 

Okay just checking...