Power mods on Sierra 1500 CC with 5.3L
I have an 04 GMC Sierra 1500 crew cab with the 5.3L engine and 3.42 gears. The previous owner added 20" wheels and tires and a flowmaster muffler, otherwise the truck is stock. My Outback 30BHQ is a...
Forum Discussion
Most of the tuner mods for gassers don't improve HP until you're way up in the rpms. Normal towing rpms will be too low to see any benefits.
