Gear ratio's for 31" tires. 4.10 or 4.56
 

Hello everyone,

New sub here.

I recently bought a 1997 Ranger 2.3l 5speed.
Upgraded the wheels to 31" BFG K1 A/T.

It's a dog in 5th gear and can barely maintain speed up a hill and lacks passing power. Usually have to drop it in 4th to get any noticeable acceleration to pass. I know the stock gear ratios for my truck are well below what they should be and with the added tire weight and height, I need something more plausible.

I've read that 4.10 or 4.56 gear ratios for 31"s are optimal, but having seen mixed reviews and discussions I'm currently in a bind as to what gears to go with. I looked at some posts in regards to gear ratios for larger tires, but they seem to be from 3-4 years ago and would like a fresh perspective.

Not planning on doing any towing, but would like to adventure out into mediocre trails and snow. I use the truck for city driving but occasionally go on highway across state. I need some advice as to what gears might fit my profile the best.


Thanks for the help

First... Look for a gear/tire matrix, most of the tire and gear companies have them.
Next, I thought 4:10s would be ok with my 33s, decided in the last minutes before ordering to go 4:56s and have regretted it but 4:56s with 31s... And only 4 Cyl, you will run out of RPMS really quickly and I am not sure how that will work out.
SO... I would find a calculator and determine the correct tire diameter/gear ratio and then go to the lower ratio... Higher number for your tire size.

Another thought, find someone with a similar truck and try it out !

Good luck

X2 on finding a gear ratio/tire size chart. They're floating around on the Internet. (Had one saved on my old phone, but can't find it now).


I'm not too familiar with what the 4cylinder guys are running for gearing. One benefit of the 4.10s is that they were a factory option, so you could just swap in a new axle with 4.10s instead of having to regear your axle (swapping is cheaper, and you may be able to find an axle with 4.10s and an l/s diff, which is another bonus).

I've seen mixed reviews. Some have 4.10 and some have 4.56

Ideally I'd like 4.10 just for the additional pickup and slightly lower RPMS.

Some say to just go to a junkyard and find a used 4.10 with a possible LSD, but I'm not sure I have the ability to put it on myself.

Was thinking on this and I think my ’95 2.3L 2x 5-sp had 4.10 stock. Two spark plugs per cylinder was a good thing too !
Power wasn’t too bad but it ran out of rpms fast.

I liked that truck great milage, but for the New England Winters it sucked !

Any of your friends have a truck like yours with 4.10s in it… try it out !

Here's a bunch of calculators I keep in my favorites but that first link should give you what you need:

Engine RPM Calculator

Custom rims, rim tire packages for your ride - RIMSnTIRES.com

https://www.wheel-size.com/calc/?whe...=30mm&scl=51mm

Calculators - Ford-Trucks.com

Differential/Speed/Axle Ratio Calculator

https://www.sizemytires.com/calculators/compare


I created a spreadsheet for my 2003 2.3L 5-spd man (3.73 gears and stock wheels/tires) for when I go to upgrade:

I used the over drive gear and a speed of 55 mph because that's about the max speed this truck sees on a daily basis. Highest speed it will ever see is maybe 65 mph.

I wouldn't even consider 4.56 til you get to a 33" tire.