tire size for better mpg
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Millerad1651
New member
You drive a brick on wheels. You can always go smaller, but the benefit would not be much at all. Plus, it'll just look ridiculous with tiny tires on it. Try a tune up and see if that helps.
I'm getting around 17 mixed with 33s, what are you getting/hoping for?
I'm getting around 17 mixed with 33s, what are you getting/hoping for?
BrianSD_42
New member
In short ... NO
For the best MPG, run what Toyota does to get their CAFE numbers as high as possible. That means the type and size of tire it came with stock. A 'P' (Passenger) rated tire, with a highway/ all-season tread.
Heavier, stiffer carcass LT (Light Truck) tires, will take more power to turn, and more aggressive tread also adds to rolling resistance, taking even more power to turn, all of which hurts MPG.
Basically anything that is a benefit off-road, (Lifts, aggressive tires, roof racks, etc.) hurts MPG.
snivilous
Senior Member
Get a front air deflector (bug guard) and rear spoiler (the wing type thing). These will push the air around the truck and then redirect it into the vacuum behind the truck to make it more slippery and get better mileage. Then a tune up as people said, and running a street tire.
JohnsD90
New member
I run 245/75/R16, On my 4runner these netted me about 1mpg better than the stock size, and they are almost identical height last i googled, but a bit narrower. Now on my 4Runner (v6 4x4 5 speed) i average 19-23mpg, hand calculated every tank. I don't think it is a problem to try to get better mpg out of what you have, not everyone wants to drive a small car. A lift won't affect mpg, you are still displacing the same amount of air. 235/85/R16 might be the best but i have never run them on a 4runner, they are even narrower, but are a hair taller than stock.
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A narrower tire will help, all other factors being equal.
A lift alone will hurt aerodynamics, and thus MPG, as parts under the truck are more exposed to the air flowing under the truck.
For example: Whereas the rear axle might be partially obscured by the gas tank, muffler, etc. on a stock truck, with a lift it's now more exposed to the airflow. On the front, suspension pieces are usually more exposed to the airflow after a lift, than when stock. With a lift the tires themselves are also more exposed to the airflow. All of Those factors increase the overall Cd of the vehicle.
I've seen it happen enough times in wind tunnels when testing different shapes for LSR cars and motorcycles, to other race teams I've been a part of.
The other thing to look at is weight. With wheels/tires you have two things to worry about: weight the engine has to move forward (like anything else on the truck) as well as rotating weight, which is a second drag on the engine.
Smaller wheels with taller tires (to get the same overall height) can help minimize weight. Alloys are also good, although I don't know what the stock ones weigh.
Taller tires can also help if you do mostly highway driving. (i.e. 70 vs. 65).
Do they make LRRs for our truck (at least for the stock wheels)?
I frequent ecomodder.com for fuel economy related stuff. You might find some valuable info there.
Smaller wheels with taller tires (to get the same overall height) can help minimize weight. Alloys are also good, although I don't know what the stock ones weigh.
Taller tires can also help if you do mostly highway driving. (i.e. 70 vs. 65).
Do they make LRRs for our truck (at least for the stock wheels)?
I frequent ecomodder.com for fuel economy related stuff. You might find some valuable info there.
inthepipe5by5
New member
My runner came with smaller tires when i purchased it. I can tell you for a fact that having smaller tires made my mileage worse due to the engine running at higher rpm to be at any given speed (which was actually reading faster due to the smaller diameter tire). Now I run 265/75 and have noticed an improvement. I went from 14mpg to 17 from this switch (all in-city, there are no freeways here). YMMV.
BlackCat914
New member
Do you have any idea how long it would take for a purchase of new "smaller" tires to offset the cost in fuel savings?
I always chuckle at that, kinda like people who decide to buy a $6,000 motorcycle to save money on gas in the summer.
I always chuckle at that, kinda like people who decide to buy a $6,000 motorcycle to save money on gas in the summer.
War Sprout
New member
You could always decrease weight! Remove the spare tire, remove the back seats, and dump the fat girlfriend. And if you live in America, statistically you could lose a few pounds, too.
Do those and report back.
:lmao:
Do those and report back.
:lmao:
inthepipe5by5
New member
For me, it was a difference of having to go to the pump every 2-3 days vs every 4-5. Gas here fluctuates between just under $5 to just over $5 per gallon It mattered.
BlackCat914
New member
So you're saying you nearly doubled your mpg by a smaller tire swap? I find that very difficult to believe.
Millerad1651
New member
He's saying he gained 3 mpg by going to a larger tire which made his truck work less, not having as high rpms.
Chandlerdoom
New member
OP just stick with the tires you have now. Now if you had 33s+ I would say sure downgrade, But the cost of new tires may or may not save you $5ish at the pump. Is that really worth the trouble of buying new tires and having them installed?
did you figure this just based on the tripometer, or did you use a gps for actual mileage? going to larger tires than stock can change your actual mileage.
inthepipe5by5
New member
Good point. I can see how you would come across to that conclusion reading my post. That logic would be correct if mileage had a direct correlation to time with all other variables being equal or nonexistent. I can say for a fact that the routes that I take or the conditions I drive through are in no way similar or equal on any given day, which actually skews the data a good bit since the requirement of having controlled conditions is basically nil. I have to drive through horrendous stop and go streets, dodge potholes that swallow just under half my wheel on both main and dirt roads, both shallow and deep mud, jungle, standing water all with the A/C on so yes, my mileage should fluctuate quite a bit. Where I did make a mistake was that I didn't say I get mileage up to when I quoted my figures. I never claimed them to double. However, I did say to the OP that his experience may be different.
This year we have been having a lot of inclement weather which seems to affect the mileage negatively. A few days ago, during the typhoon I noticed that from full tank to half I only got 112 miles where the week before in the rain I got 126. During mild dry conditions in the mid-upper 80's with no rain I can get around low to mid 150's on a half tank. I have no other way to explain this than to think that a combination of the increased barometric pressure/humidity, low speed, needing to engage the multi-mode AWD and in some cases locking the center diff all contributes to the horrible mileage. Even when driving in the rain in 2wd I will notice a drop in mileage.
As a side note, as I read your comment again, I think you have it the other way around, I actually got better mileage going up a size, not down one. I still welcome your insight as to why my mileage would fluctuate so badly.
Yes, this was the point I was trying to get across.
I did the tripmeter for the mpg calculation. My GPS did not have any working map for here so I sent it back to a friend back in the US. I've tried using the ones on mobile phones but the data service here sucks so I can't get a reliable connection to measure with. After a while, and several gas price increases (went from high 3's to above 5, then back down to sub 5 all in less than 2 years) I stopped trying to figure it out and just notice when I go back to the pump.
I agree with your statement, but as I have not actually run stock tires, I can only comment on my experience between the smaller size and the 265/75 KM2's I'm running now.
Just make sure, no matter what size tire you get, that you pump them up! I usually go 5-10psi over what the manufacturer says in the glove box/owners manual/door jam, but no more than the tire rating. The only reason for the car limit is for comfort, more so than safety, so maintaining within tire spec is of more importance. If you have aftermarket parts like shocks and whatnot, the OEM is of even less importance.
There is a point where pumping them up will cause worst gas mileage, but you will have to experiment with that (just do 5psi changes over the course of a few tanks to see what you get).
I don't recall what you said most f your driving was. City, highway, dirt roads?
There is a point where pumping them up will cause worst gas mileage, but you will have to experiment with that (just do 5psi changes over the course of a few tanks to see what you get).
I don't recall what you said most f your driving was. City, highway, dirt roads?
FancyPantsMcGee
New member
I 2nd the 245/75r16 option, I ran those on an all factory 98 4runner for a few years. looked as normal as the rest of them, and consistently got 22-23mpg.
