There I do run syn. I've been using 75/90 Mobil1 for a few years and when I get done installing this traction bar am going to refill with the same weight Royal Purple. PITA finding enough of that stuff around town to do two diffs, though, so it'll have to be some good stuff for me to go to the hassle of finding it again. I've never noticed any appreciable drag with Mobil1. With conventional Valvoline in the cruiser on the other hand...egads.

~Adam


96 T100: D44, lockers and stuff