simplysmn

I would go 410's I had 325-85 R 16 michellin's on my last truck and it had plenty of get up n go

93-12Smoke

I am running 4.10's with my 33x12.50's and I think it is to low for highway driving, but it is greared to pull. The truck tops out at about 83 mph. So 38's to 44's with 4.10's would probably be good highway and daily driving gears but if you want to pull I might go with 4.56's.

Mieser

After driving the truck around with the 265s and 3.55s I am heavily leaning toward 4.10 gears with the 325/85r16s. That is also one of the most simple options cost wise.

Its good to hear about someone else running the 325s with 4.10s.

4.10s will gain me a few rpm's over the 315s/3.55 combo I was running.

Crossy's son

I've riden in a few second gens with 3.55's and 35-37" tires and they pull fine.

Then again, I'm thinking on road, Not much offroading around here, When you get bigger tires the lower gears are just nicer to have for offroading and acceleration I guess.

Mieser

I need a balance between off-road ability, on-road, and towing. This truck is going to do it all. It's suppose to be a cross between an expedition style truck with a little desert and rock crawler mixed in, hence the low CoG with big tires.

Its good to hear about people having good luck with 4.10s and big tires.

powerrammaster

I have 4.10's with taller tires and a 5 speed and I thought the size of tire would negate the the gearing, but it doesn't too much. i lose 1 st and second as they wind out pretty soon. I have another truck with 35's and a 5 speed with 3.55's and that is a little luggy but not too bad. i guess 3.73's would be just right if they're available.

92roughstock

3.73 are available for each end of our pickups.

I think if you are running a near stock engine, you should be just fine with 4.10s and your 38-40s and some mild tuning. Get some gauges, and turn your power screw in a turn or two, and see what happens. Keep in mind that bigger/ wider tires = more rolling resistance, which can lead to drop in MPGs.

Keep the Getrag 1-1.5qts over stock, and the RPMs above 1500, and it should last a while.

1985cucv

i would rock the 3.55's myself i wish i had them! 4.56 with an auto 75 maxed out