Hey can anyone clarify whether or not a 3.08 gear set will work in a 2.77 9 bolt rear?

I have searched on here and 9bolt.com and have found varying answers on this.

Thanks in advance!

No, 3.08's go on a 3 series carrier on a 9-bolt.
On a 2 series on a 10-bolt.

Their sales page has the answer you were looking for.
http://www.9bolt.com/gearsets.html

All but the 2.77 ratio are suitable for use with the 3-series carrier.


2.77 use with 2-series carrier


3.08 use with 3-series carrier

And so on for the higher gear ratios, all using the 3-series. No other ration uses the 2-series that the 2.77 uses.