I have a 1994 4runner with 31X10.5 tires
The grear ratio is 4.88 I think. The axle code is G144.
However, the sticker on the door says 225.
I'm thinking about putting 235's on to improve gas mileage
Anyone have any thoughts?

 

31's are a 265, the stock size for a 2wd ford ranger is like a 225... thats a 26 i think or 27

 

You should see a slight increase in gas mileage around town, but your hwy RPM's will increase slightly yielding worse fuel mileage. (In theory anyway..)

 

just dont stomp the gas and youll be alright

 

On some models the stickers all say 225 (the base tire) regardless of which tires actually came on it.

 

If your truck is geared with 4.88s, then it is likely an automatic tranny that came with the factory 31" tire option, so you would be geared properly for that size tire. Alonst every Toyota 4WD pickup and 4Runner comes with that same silly 25575R15 sticker in the door jamb, even if they were equipped with 31s or even 16" wheels from the factory. I guess don't believe everything you read.

 

On one of the sites that breaks down the codes they mention that either US built or JPN built rigs has only the 225 sticker and the other has the actual tire size. Don't remember which.

 

Thanks for the responses.
I still don't know which tire size to go too next.
Here's what I noticed today.
I normally drive 55 to 60 MPH going to and from work.
Today I took a road trip where I got my speed up to 75 for an extended period of time.
I filled up at the beginning of the trip and I guessing that my gas mileage will be somewhere around 20MPG at least. (3.0 V6 Auto with lockout hubs)
I noticed this on my 92 runner as well. I got better mileage at higher speeds than lower. I have more torque at higher RPM's also. I think that the 3.0 liter engine was built for higher speeds and performs better above 3000 RPM.

Anybody else notice this? Also I do most of my driving above 7000 feet.

I'm going to modify my air filter "tub" with more air getting into the filter by drilling holes in the tub and adding another external filter to the inside of the tub. I bought a furnace filter for this and am going to sandwich it between expanded aluminum mesh. Haven't decided whether to install it on the inside of the tub or outside.

My 92 runner had a K&N cone and got 24mpg. I think the secret was it allowed more air coming into the air mass meter. Not that it did a better job of mixing the air with the gas. K&N's have a poor filtration record though so I'm not going to replace my OEM paper filter.

I still don't know what to do with the tires???