OCHOA505 A 4l60 should have no removable inspection cover, it would like a big watermelon slice if it was there, if it does have that then you have a 80e, squiggly lines in stamped into the bottom of the pan are a giveaway also that it has a 4l80E, I have a cammed 5.3 1500 that is DBC and i have the same hesitation issue with the 3:73 gears and 33" rubber, but it gets slightly worse whet the motor reaches operating temps, cold starts are no problems, i ordered a YANK TT3000 and that solved my problem