General Tech What engine oil do you use and why?

[LT.]

Royal Purple in the Hemi and in the Escape, because both vehicles seem to respond well and get better mileage then they did on other oils. In the Cummins I use Valvoline Premium Blue because it is recommend by Cummins for use in their motors.

LT.

 

[N-Smooth]

-mobil 1 full synthetic in the acura
-cheap and thick stuff for the xj (usually autozone or walmart brand 20w50)