Howdy,
I put 75/90 Fully Synthetic PAO stock based in mine w/friction modifier. I do have the TractionLok/Posi w/3.73 gears and a 9" Billet Stallion 2800 stall torque converter that puts approx 40% more torque to the rear tires. Tuned torque modulation, shift firmness and rpm times. If you're...