Differential Lube Change Interval?

[EddieC]

What is a good change interval for '08 Tahoe differential lube changes, both front and rear?
It doesn't seem to be a high priority in the manual but I have to think there is some good to come from changing it.
I have a rear locker and I've read that the spec'd GM 75W90 synthetic lube contains the limited slip additive, but comment on that would be helpful too.

 

[OR VietVet]

I would change at 50k miles even if the manual says differently and is likely closer to 75k to 100k miles. Your manual will tell you what fluids to use and I would stick with that. I do.

 

[Foggy]

Any brand of synthetic gear lube is fine.. You can add the little bottle of
posi lube to the rear for good insurance- it won't hurt anything if its "already in" the
gear lube of your choice
And 50K is the very most I would do on any Differential.
Dont forget your transfer case and transmission fluids..
Transfer case is very easy.. Don't know for sure which fluid in it, check out manual
or have the parts guy look up the spec for your app