gear ratio dilema

[biggsteve97]

I have a custom built 87 Silverado 4x4. With a custom 3 inch lift 32" tires, 330hp 350V8, NV4500 5 speed manual trans, dana 44 front and corporate 12bolt rear with 3.73 gear. I am in the process of building up a corporate 14 bolt full float axle with disc brakes for the truck. After tear down and inspection turns out it needs more than just bearings. After close inspection of the ring gear I found a chipped tooth and several rusted and pitted teeth. I am planning on putting 33" tires on soon even debated goin 35" tires. Truck ran great with the 3.73 gear on 32" tires so my dilema is should i just replace the ring and pinion with another 3.73? Or is there a better ratio that would work better for my setup? I realise that if i swap gears in the 14 bolt im building i have to get a matching gear for the front.

[Ziegelsteinfaust]

The bigger or taller the tire the more rpm you want your engine to turn to help power the truck.

Normal 32" tire 2000-2200 would likely provide maximum cruising mpg. Extreme mud terrains 2500 rpm would likely be the sweet spot. The taller the tire the higher rpm becomes less of a negative then on street tired truck.

So I would decide on tires before you decide on gear ratio's.

[bilfman]

I have overdrive and 32s I totally recommend at least 4.10s . I have 3.73s but the extra 10% from 4.10s would make it near perfect. I wouldn't rule out 4.56s if you like pullin.