Truck built for speed

short legs for pulling, long legs for running. with that rate. i would say low pro 22.5 and 3:55 legs

 

Depends on era of engine. Best to follow engine manufacturer gearing recommendations. What engine we talking?

 

Big horsepower & long legs. Making mts into mole hills.

 

3.70s tall rubber and you got a triple digit truck

 

100 mph with 3.70s you're gonna be screaming to hit 100

 

Calculator says 2075rpm with .73 top gear.

 

It does depend on the engine but my vote would be 390 Rears.

They are low enough to give you the grunt to pull up the hills but they're high enough that you can Cruise.

With 390 rears at 65 my truck is turning about 1550 or so.

At 80 miles an hour not sure about rpms, but I still have plenty to go.

Now if you are out west and the speed limit is 75 where you often travel and you want to cruise at 80, you probably want to be geared a little bit higher or maybe have a double Overdrive.

 

The other option is to put in a auxiliary.

 

The truck im my avatar has Lo Pro 22.5 and 3.91s behind an old school .62 dbl over. According to gear calc i can do 103.13 at 2100 LOL