You can use any oil that meets the minimum specs. The slick kind is preferred :badgrin:
I and a lot of others are partial to Delo 15w40 and just a couple of days ago I saw Mobile Delvac 15w40 on sale for $9.95/gallon
both are terrific oils for the 1500 transmission.
(By the way,,,,, what the heck happened to this forum????)