01 7.5 Differential oil

[Conflict]

manual says 80w90. autozone has no 80w90 synthetic. Can I use 75w90 synthetic? Tech page just says to use 80 or 90 oil. It's an 86 code so it's not limited slip. I'd like to have limited slip but the F axles have a small offset. Does that mean they are not a drop-in for my 2001 B2500?

 

[alwaysFlOoReD]

As far as the oil, 75w90 is fine.
I don't know about the f axle.

 

[Dirtman]

Never even heard of 80w90 synthetic. 75w90 is the synthetic equivalent. Either way, either one is fine.