I am considering jumping from a 31/10.5 to a 33/10.5 tire on my stock 15 rims. I have a 4 inch lift on my '91 Runner and from what I have read it doesn't appear I will have any rubbing issues. Since I am only going taller and not wider am I going to see a significant drop in power and fuel economy? I am not planning on regearing.

Thanks.

 

Yes you'll see a diff in power, (actually quite a noticeable one). No you shouldn't have any rubbing issues, but its the diameter of the tire that screws up your gearing, not the width that just adds drag and friction. Try it and you may want to look into regearing in the future. What motor/transmission do you have?

 

I have the V6 3.0 liter 5 speed. When I bought it, it came with the 31's. Its not fast but not completely gutless either. Sticker inside the door said it came stock with 225/75/15. I assme those are like a 28/9.5 inch tire or so.

If I won't be able to reach 90mph then forget it, but I was thinking that a taller tire would be close to my current efficiency. I average 15-16mpg.

Please inform the ignorant.

 

Not exactly the same thing, I have the 2.7l 4cyl (about the same hp as your 3.0) with the 5spd in my 97. Went from the stock 225/75/15 to 235/85/16 revos, which tirerack lists as being roughly 32 x 9.5. Really didn't notice much difference, still have stock 4.10 gears. on a recent 2000 mile road trip I got 21-23mpg, avg speed between 65 - 80 depending on the state. I used GPS to track speed & distance since my speedometer is about 10% off. As for power it was pretty good, cruise held my speed in 5th on most hills, except for WV where I had to hit 4th a bunch & 3rd a few times. Oh, I don't have any lift yet.

Hope this helps a little.

 

I run the 33x10.50s, work great:

http://www.4crawler.com/4x4/BFG_AT_KO.shtml

As noted, no problems rubbing, you will see a 6-7% loss of torque to the road with the tire size change.

 

I run the same as well--perfect combination. My truck came with stock 4.88 gears, so it made almost no difference. I actually get the same mpg as with the 31's I had before, and power difference is almost none--it didn't have power before, and it still doesn't.

 

http://www.cardomain.com/id/viv4runner

33x10.50 BFG MT on 15x7 alloys... no rubbing with 1.5" BJ spacer and OME stuff

I wouldn't trust the sticker on the door jam. Take your VIN into a dealership, tell them you need a new ring and pinon... and with that you can figure out which gears you have.

 

I have 33x12.5's, but its still pretty close to the same power loss. After I put them on it was noticably slower. On the freeway I could hit 75, but after I installed my 4.88's I can cruise at 75 no problem. I can can go faster, but in my truck it rattles and shakes so much it gets kinda scary.

 

i went from 31x10.5 stock rims to 33x12.5 had slight rubbing issues (but nothen major) 22re had a big loss in power. really, its just hard to find the right gear...i'll hit 2nd in turns and it just dosnt feel like its the right gear, too high of a speed for 1st, but too low for 2nd.. had a bit of drop is gas milage, good drop in tourqe, but as soon as i took it to the dirt/mud....then i knew my investment was well worth it! The bigger the better!

 

What type of 33s are you looking to run?