A few years back I had an 00 silverado with the 5.3 and 3.42 gear set. Pulled a small 5ver around for a few years. Thought to myself.... Hey let's go spend some hard earned cash and throw an performance exhaust on this baby and opener up to breath..... Well that was the plan anyway, after the installment of the custom free flowing exhaust I ended up losing mpgs.... And towing well to say, it was very unerving listing to loudness of being in 3 rd gear all day long with the rpms up... So would I do it again...nope... Except on a fun toy ( race car)... Anyway keep it stock, change the gears if needed. The 5.4 of that era did not have a huge amount of power and in the expy...it feels kinda slow towing, ( personel experience ).... Regardless of the hp and TQ rating that engine will last u a long time....
