Axle Ratio with 31's and 4 cyl

[spencersausser]

Any suggestions on what gear ratio to run in my rear axle if I want to run 31 inch tires? I have a 97 4r with the 2.7 liter 4 cylinder engine. Everything is stock and I want to do my best to keep the gas mileage as close to stock as possible. What's a good axle ratio for this? Any suggestions will be much appreciated.

Spencer

 

[ChildrenOfBodom]

Any suggestions on what gear ratio to run in my rear axle if I want to run 31 inch tires? I have a 97 4r with the 2.7 liter 4 cylinder engine. Everything is stock and I want to do my best to keep the gas mileage as close to stock as possible. What's a good axle ratio for this? Any suggestions will be much appreciated.

Spencer

We need a few more things from you.

Automatic or Manual? 2WD or 4WD?

 

[spencersausser]

We need a few more things from you.

Automatic or Manual? 2WD or 4WD?

Oops. It's a manual tranny 2WD.

 

[ChildrenOfBodom]

If you're just going to run a 31" tire, consider going to a dismantler and buying a 4.30 rear diff. That's essentially like doing a 4.56 in an automatic. You won't be exactly at stock, but you'll be really close.

Go on Car-Part.com--Used Auto Parts Market. Look up 1997 4Runner Differential, then choose whichever ratio you'd like for the rear. It will give you results of places that have the item you want, and you'll have plenty of choices in price.

4.56 works, too. That'll help you more in acceleration, but that's like putting 4.88's in an automatic. Most would say that would be overkill for 31". Your RPM's will be higher on the freeway, but that's not really going to make that big of a difference. I wouldn't do 4.56 in your truck unless you want at least a 32" tire. Again, available on Car-Part.com--Used Auto Parts Market, for much cheaper than a rebuilt unit or new gears alone.