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...
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The 20's are what's killing you.
If going to 4.10's only gets you UP to 1800RPM at 60MPH, then your tires are way way too big around.
My 3.42-geared truck turns 1900RPMs at 65MPH on stock 16" tires.
It will also improve your gas mileage by about 20% because you won't be downshifting at every puff of breeze or every slight uphill.
If going to 4.10's only gets you UP to 1800RPM at 60MPH, then your tires are way way too big around.
My 3.42-geared truck turns 1900RPMs at 65MPH on stock 16" tires.
It will also improve your gas mileage by about 20% because you won't be downshifting at every puff of breeze or every slight uphill.
