i have 37s on my 94 f250 with a 351w with stock gears and its just usein to much gas just for it to get up and go so im just wonderin what would be the best gear ratio so my truck can get up and go quicker and to save some gas cuz its bad enough already

 

4.10's or a 4.56 gear.....

 

iv been told to get the 4.10s . my truck will barely even spin the tires in dirt

 

4.10's are better for 35'' tires....the 37's will need a tad lower....SO I would recommend the 4.56's...Just to be sure...lol

 

well im gonna need new tires really soon and i think im gonna go to a 36x15.5R16 so what would work good with that?

 

UGH....Idk on that...I guess since it's in between 35/37's....Its a either/or situation...lol

 

4.56 will get you in your "close to stock" rpm at a given highway speed. 4.88 will get you more POWER less gas milage. the rule of thumb for tire to gear ratio calculation is to multiply .12 by your tire diameter. (.12 X 38" = 4.56)

my 96 ZJ has 37" tires and i run 4.56s and i have pretty good get up and go go

check out 4Lo.com :: Gear Ratio & Tire Size Chart

 

What transmission do you have?

There is no one stock gear ratio you could have one of several options, but that said the ideal power vs fuel milage ratio with stock 31" tires is 3.55 to 3.73, and to get that with 36" tires you need 4.10 to 4.30.

Also of high importance particularly if you have the E4OD trans is that the PSOM(speedo) be recalibrated for the larger tires. The computer controls this transmission with input from all sensors including the speedo and an accurate input is vital to proper trans operation. An accurate speedo will also improve fuel milage simply because if it's not recalibrated you're actually travelling faster than indicated which burns more fuel, and because the odometer isn't racking up as many miles as it should.

 

yes i have the e4od transmission. im just tryin to get some things done to my truck so i can get better mpg because im only getting around 11 to 13 mpg

 

Ditch those 37" tires. Good gas mileage and big tires do not belong in the same sentence. Go to something more reasonable like 31" to 33" tires. All the money you would spend on gears could be saved by going to a shorter/narrower tire.