Better MPG with 235's ??

[ebutlerfj40]

Time for new tires on my 00 4Runner. SHe's got old PP springs and Bilsteins on all 4 corners, 3.4 auto, 185k on the ticker, & bald 275/70's. Job change has me doing a lot more driving and I'm being paid mileage, so I want to get the best MPG possible. Anyone have experience with the 235/85R16's? They all seem to be 10 ply and I am concerned about the ride quality. What about 255's? Any other suggestions for better MPG would be appreciated. BTW, I am running Amsoil from nose to tail, deck plate mod, K&N, and engine is running great. Got 19.6 today driving mainly hilly highway - would love to get 21-22+. Thanks

 

[FlatlandTRD]

The 235s will work fine, you may gain 1 mpg or so due to the decreased rolling resistance. The 235s (~31.7)are almost 2" narrower than your 275s (~31.2), and about 1/2" taller. The weight savings is only a few pounds. You shouldn't even consider the 255s(~33.3), it will zap the power and economy.

The reason the 235s are 10ply (E) is because they're generally a dually tire, used on the tonners. The ride won't be much different, it's all about the right psi. Plus the 235s are cheaper.

I'd say you can come by and drive mine Eric, but since I'm regeared it really won't help. We could slap mine (255s) on yours for fun, but I think you'll like the 235s more.

 

[hoch]

I'm on 235's. The MPG gain is virtually none compared to 265/75's. Compared to stock, I'm about 2mpg off. I was getting 21mpg stock and now get 19-20mpg. Might be about 1/2 mpg better than 265/75. But it's MUCH cheaper than 265/75's. I have BFG's (Load range E) and the ride is good. I really can't tell too much difference from the stock p-rated tires. Great tires. If the prices of 235 and 265 were similar, I might have gone with 265's. But I wasn't going to spend an extra $200 for 265's. Overall, very pleased with this size.

 

[ebutlerfj40]

It sounds like there isn't much difference in the mileage on the 235's & 265's, just initial cost. I like the looks of the wider tires, but am willing to sacrafice that for better mileage. Jason, I think you're right about the 255's - certainly not enough power or gear to turn them. Any others with opinions or experiences on this?
Eric

 

[Duane]

Well I have run a set of 235/85R16's Michelin LTX M/S They are an E load rating..10 ply tire. I recently bought some new tires and went back to the factory P265/70R16's.
I recall when I put the 235's on that I didn't notice a change in ride but now that i went back to the factory size passenger rated tire ..wow..much smoother.
The overall height is about an inch difference and I think this definitely affects your mileage. For what it's worth a Michelin tire is also typically a smoother riding tire than most brands so an E rated tire in say a GoodYear is likely going to ride much rougher.

The stock tire is a 30.7 inch tire. The 235's are almost a 32 inch tire. If you want a LT245/75R16 is a 30.7 inch tire and the width is in between the other 2 options. I think a 245 can be bought in a D or E load rating as well. If you go to a 265/75R16 they are basically a 32 inch tire the same width as the factory 265/70R16's.
If you are concerned about mileage do not buy a taller tire and if you go to a narrower, smoother tread design you should reduce the rolling resistance of the tire, thus best chance for better mileage.
Michelin LTX M/S are excellent tires all year round, wear well and forever almost, are quiet and balance up with usually minimal weights. Check out the tire reviews on Tire Rack for any tire you may consider.
Here is a link to Michelin tire size chart. MICHELIN | LTX® M/S | Tire Sizes & Specifications
There are several smaller size options in a 16 inch as well. Going too small can bring up you rpm's to get the same road speed though so there is a limit.
that's my 4 cents

 

[Jetboy]

IF you want better mpg, buy some P rated tires. I have a set of FJcruiser take offs which are the 6 spoke 17's with P265-70-17's IIRC and I get around 22mpg on the highway. I actually did a 220 mile trip last summer with the cruise set down at 65 and got right at 25mpg. I only get about 19-20 max with my stock wheels and Load Range D Yokohama's. The lighter weight and lower rotational inertia as well as lower rolling resistance of P-rated tires makes a big difference. Plus they ride much nicer and are quite on the highway. And then I'm not wearing out a more expensive set of tires just cruising the highway. I have the landcruiser for wheeling so my 4runner is mostly a highway/light offroader anyway. Oh and I paid $500 for the wheels and tires with 1,000 miles or so on them, which is probably less than you'd pay for a set of tires. You could probably find a similar deal.