Gear ratio question. please help 37s on F150

[deadweight]

Hey guys I am running 37 on my 04 F-150. I need to know what gear ratio is best to run with this set up. I drive the truck everyday and it dosent see very much off road, I jus think that it could do better. Also what impact will new gears have on my crapy fuel mileage? Thanks for any help.

[c_rock]

I've seen calculators somewhere but cannot seem to find them now. I would suggest 4.56 or something close to that. I put 4.10 in my Suburban with 35" tires, and it just isn't quite enough for my likings. I'm thinking that your truck is lighter than my Sub, and is turning a little bigger tires, so 4.56 should be about perfect.
You should post up in the Ford section to see if someone there can give you more specific advice.

[GerryK61]

If your running a 5 speed manual trans Or a Auto with overdrive I would go 4.88.

[riverrat]

I had the same question and put in the Ford Section, I ended up finding this table that help me better determine what was needed. Link provided below.

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

~RR

[Dale813]

Dont know what you should run but I have 37" Swamper boggers on my 1986 Toyo 4x4 pickup with a 4 banger and I have 488's. I should have 529's.