Banned from GMFS
Mar 20, 2011
Ok so figured I'd post this up here. People that lift there trucks usually put bigger tires(even the cencal guys do eet). Well a nice upgrade you can perform is to swap the gears out in your differential(s). You will gain better performance, some fuel mileage, and probably save your transmission from being cooked.

This is a normal gear/tire chart:

Yellow: Geared more towards Highway Driving
Black: Middle Ground for a Mix of Highway/City Driving
Blue: All out performance and City driving

Now this is good for 98% of people that lift their trucks.

Some though, prefer a little deeper gear(numerically higher) for around town driving because they do not do much highway driving. So best thing to do then is to follow this chart:

33s - 4.30s or 4.56s
35s - 4.56s or 4.88s
36s-40s - 4.88s to 5.38s

I personally run 5.38s in my truck with 38" tires. It has alot of get up and go in town and doesn't rev too high on the highway(75ish is around 2500ish RPMs).

When you run deeper gears you basically have to figure out a sweet spot based on engine/tranny mods and tire size.
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