New Wildpeaks and MPG

Interesting that the difference in max load between the two is about 24% which is close to the reduction in mpg OP mentioned. Could be just a coincidence?

 

I went from stock 245s to Wildpeak 245's, SL rated, MPG avg went from 22.5 to 20. Most of my driving is on smaller roads 50-60mph

 

OP, you went from 245/75R16 to 265/75R16, so you're an inch larger in diameter with 3/4" wider tread (more rolling resistance). Additionally, the new tires are heavier (especially if you went with E load). Give it some time though to see what the real difference is; one trip is not a good indicator.

 

Sounds like you got the heavier E rated tire if you're seeing such a drastic difference from stock. I switched to SL 265/70/17 Wildpeaks and I am still able to get 21-22 mpg at times, that includes a slight lift and sliders on the truck.

 

My SL Wildpeaks give me around 20-21mpg.

 

Best detailed explanation by far. About the only thing OP can do at this point aside from changing back to OEM tires is to pump them up to 45-50 pounds and see if that makes any difference.

 

Just did my 28 mile commute on my new wildpeaks. Same size as OP but SL. Got 21 mpg which is pretty much what I always get although it varries from a low of about 19 of in the winter to sometimes 26 in perfect conditions. Also add back the 3.3% and very respectful mpg. Still on my first tank with these so will have to wait until I fill up to get a good average.

 

I have LT265/75/16 E rated tires on my 07 Tacoma. They are 15 lbs heavier each compared to the factory P rated tires and are bigger to boot. Fuel mileage and performance is still exactly the same as it was 12 years and 197,000 miles ago.

Rolling resistance is mostly due to tread pattern and air pressure. I run closer to 40 PSI in my tires and don't have a tread that is as aggressive as the Falkens.

The OP's speedometer and odometer is off slightly too. He is driving faster and farther than he thinks. Once the actual miles is determined he'll find that he is doing a little better than he thinks. And when he slows down a bit he'll see an improvement too. And I'd add 4-5 PSI to each tire too.

 

curious at what you might recommend for a tire pressure? I run a similar setup with a 3 inch lift on my mall crawler with about 40 PSI and it's pretty rough.

 

Cool...thanks

 

I have the wild peak 265/75/16SL and get 21mpg
When I ran KO2 same size in 10 ply I was getting around 18mpg.

 

With skid plates, sliders, a lift, bigger wheels/AT tires, and usually an RTT in the bed, my truck runs *about* 16 mpg (more or less) on my daily commute in bumper-to-bumper, stop/go traffic. So this totally sounds right to me. Obviously I getter mileage when travelling downhill on the highway with no traffic. AT tires are going to create more friction and resistance... that's like the whole point of having them.

I don't normally comment on MPG threads, but OP seems cool.

(edit: I just back-read some of the posts and it sounds like you're running 10ply/E tires, so that's an additional weight tax. I got 6ply/C, my logic was that I only dream of doing cool things and on most days I'm just slogging to work and back)

 

Headwind vs tailwind. I certainly notice a difference in MPGs on this alone.

 

doesnt the truck come with 265's already so 265/70/16 to 265/75/16 is a small change not the 245 (or am i wrong?)

 

My average is from the average MPG calculation on the truck from the past 6k miles. One tank of gas is meaningless. Ive done the math before for a full tank and the truck computer is very close to accurate.

 

That happened to me initially


1st road trip about 16mpg


2nd road trip a few months later and it was 18.9 average


Wife’s 4 runner has 265 70 17 which is the exact same diameter as 265 75 16 and she gets the exact same gas mileage 18-19


You have 2 things going on here


1. You have changed the gearing by moving up a size


2. Weight. Even though your tires are on the light end of its size they are still heavier than stock


Most who report that they did not notice a difference either have a heavy foot or got a lightweight 17" rim (makes a huge difference on weight) and with a 17" tire is weighs less because there is less sidewall.


I believe that is pretty much it.


I am going to leave gearing out as it is not really in most people’s budget.


Maybe try resetting your ECU by unplugging the battery for a minute. Then step on the brake pedal a few times for about a few seconds each....this will make sure any residual power stored in capacitors anywhere will be drained. When you attach your battery your computer will have to relearn. ----The battery is just a suggestion.


What model do you have?


If you remove the plastic chin (if you had one and if you removed it) try putting it back on. I have not done this.

 

haha. I did exact math once, but nowadays I just remember to add about a mile every approx 30 miles or so. ish.

 

I get 20 on distance trips with the same tire in 265/70/17 at 34psi with armor, lift, etc.

But, OVTune helps a lot

 

Should have listened to me and got the (C Load) 265/75/16 Duratracs! Can't go wrong with a Goodyear!

 

these are the ATs?