Every Durango I've ever seen has had the 9.25 axle under it. I assumed this is because every durango I've ever seen was also a V8. I know V6 was possible, but how many did they make? 3?
when it comes to the Dakota's there really was no rhyme or reason to it...although there is a slight pattern that indicates V8 trucks are more likely to have the 9.25 than V6 trucks.
I grabbed an entire 8.25 axle out of an 03 4x4 that was a V6 automatic, just for the rear discs, and swapped them onto my 9.25 from a 98 R/T.
Manual transmission trucks seemed to have a higher liklihood of getting the bigger axle as well.
so if you had a V8, 5 spd, then it most likely had a 9.25 under it.
my quad cab 04 has a factory towing package on it, so it has the 9.25...however, only 3.55 gears. I had an 05 Durango that had the factory tow package on it, which included 3.92 gears.
