After some research, I'm considering an upgrade to mud tires on my now stock '99 4WD. The stock tire size is 265/70R16, but I can only find mudders in 265/75R16. I'm guessing the extra inch of difference in diameter won't be a huge problem as far as clearance is concerned, so my concern is about a decrease in usable power. The stock gears are 4.3, but I'm not sure how the additional inch will affect highway driving. Will I experience a significant change in acceleration or highway cruising ability (i.e. steep inclines, high speeds)? Thanks.

 

With 4.30's, you should be in pretty decent shape. You will notice a difference but I doubt it would be major.

 

i put 265/75/16 BF Goodrich A/Ts on my '98, up from the stock 265/70/16s and i haven't noticed anything. they aren't mud tires like you want but i thought i'd share that i haven't had any problems going a little bigger. i do some highway driving, not a whole lot, but it still feels the same as with my old tires only i get better traction.
patrick

 

Thanks, guys. I'm feeling good about stepping up to bigger tires.

 

Kev, try looking online at places like www.offroadwarehouse.com and www.4wheelcustoms.com to find mudders in the size that you want. 32" is by no means the largest they make them in.

 

I know mudders get much bigger, but I think 265/75R16 are about as big as I can fit on a stock 4Runner. I wish I had the money for even bigger tires, a lift, new gears, etc. I guess I'll have to settle for the mudders that fit.

 

i went from 265 70 to 265 75 with out any notice in acceleration or gas mileage, plus yours being a 99 4wd you can clear them no problem mine sets 1.5" lower. good luck with your decission

 

Ditto on not noticing any change nor having any clearance issues going form the stock 70's to 75's. I keep detailed fill-up to fill-up fuel mileage records and barely noticed a noteworthy change. Note that the extra ~ 1" diameter results in 1/2" of additional height.

 

I had no problem putting on 265/75/16 on my '01. Mileage may have gone down a bit, but no more that 10 miles per tank. Power loss is negligible if any. Good luck!

Kent

 

That inch difference in diameter translates to 1/2 inch each side on technical specs. The real tire is usually less than specs when you add vehicle weight, etc. Take that, with the fact that over time tread wear reduced diameter.....

I doubt you'll notice a difference even if you tried.