Kaapo

I have ls1 trans am. 90000ml driven. Which oil is better? Red line 5w30 or 10w40. I only drive in the summer.

86Tri-z

stock ls1 is 5w30 I have never used redline in a car only their 2 stroke oil. I’ve always ran mobile 1 in mine

grinder11

iTrader: (1)

I agree, and would recommend 5w-30-UNLESS you are tracking the car. In that case, I'd go with 0w-40 Mobil1. In no circumstance would I run 10w anything-UNLESS you've got a built motor with greater bearing clearances than the SBE calls for. My .02.