I've got BG 44K in both vehicles right now. The 4R is running more smoothly and hard to tell if its running at a stop light. I haven't noticed anything with the 5.0, but thought I'd run it through regardless. More expensive than most other products, though. In my old '93 pickup, I noticed a difference on the way home right after putting it in. Smoothed that 3.0 out quickly and enough to notice.