How much does tire weight really affect performance/mpg?

Here is my dilemma, I got a great deal on a set of Falken Wildpeaks 265 70 17 @ 47 pounds

I currently run BFG Rugged Terrains 265/65/17 which get great MPG and are about 4-5 pounds lighter, how noticeable would this be?

I drive a lot of miles every year and I don't wanna bog down performance too much. I read about the Hankook Dynapro RF10 having decent rugged looks and being about 37-40 pounds depending If I get 65's or 70's so not sure if it would be worth looking into a set of those and selling these which could potentially be 7-9 pounds lighter. Any other suggestion for a set that's around the a similar pricepoint as the Falkens?

 

Everything else being the same, you'll probably take around a 5% mileage hit going up in size and weight.

When I went from 265/70R16s OEMs to 265/75/R16 Wildpeaks, I saw a very small mileage drop, definitely under 5% so you could probably expect the same. Make sure you look at the OD of each tire and calculate the conversion so you track mileage right. Your MPGs will be off by the % difference in tire change.

 

Here is a great source of tire info for you... in your situation, current tire is in position #1 and proposed change is position #2... the circumference will be 3.3% larger.

 

Keeping unsprung weight as low as possible was a big consideration for me. I went with the Wrangler Ultra Terrains sold by @Discount Tire Direct over the Falken WPs due to them being lighter. No noticeable road noise, great wet/dry traction, deep tread/aggressive sidewall, lightweight (265/75/16 SL is 40lbs) and good looks!

I was in the same boat as you for a looong time trying to decide on a AT tire, these fit the bill perfectly.

 

You have to remember the tires have to rotate (obviously) but rotational weight makes everything different. Here is a site that explains it pretty good without going too deep.

https://www.cjponyparts.com/resources/what-is-unsprung-weight

 

I'm at the age that I do not worry about the price of gas. I fill-up and don't even think about it....in fact i never bother looking at the total.

 

Thanks for the links guys and MPG wasn't my main concern, but the power loss/gain when I could get tires around 7 pounds lighter although I just did a quick calc on a website and losing 1-1.5mpg would mean around $400 more in gas during the lifetime of these tires so I thought why not pay for that upfront for lighter and potentially higher quality tires..

 

The heavier it is the harder it is to spin up, and the harder it is to slow down. How much, idk. But once spinning, a heavier tire will have more momentum. So that energy isn't all lost.

All of this is to say, it probably matters more if you do a lot of City driving / stop-and-go and less if it's mostly highway.

 

Cool story bro

 

https://www.cjponyparts.com/resources/what-is-unsprung-weight

That article deals with shaving 200 lbs off of a race car's unsprung weight in order to make your car 1/10 of a car length faster in the 1/4 mile. Saving 4-5, even 10-15 lbs per wheel won't be noticeable at all on your truck, it is all theoretical. I'm on my 5th set of tires for my 07 Tacoma. I've had P series tires that weighed 38 lbs each, E rated tires that weighed 53 lbs as well as some in between. My fuel mileage and acceleration are the same today as it was 195,000 miles and 12 years ago.

Going to a larger diameter tire robs power and may reduce fuel mileage. It also makes the brakes work harder. But generally if you go no more than 1 size up it isn't enough to notice. Tires with aggressive mud tread have a very high rolling resistance compared to All Terrain or street tires which will hurt fuel mileage. They don't make lightweight P series tires with aggressive mud tread.

The problem is that most people who go up 1-2 sizes, AND to to an aggressive tread tire and see a reduction in fuel mileage. But the loss of performance is because of the larger size and tread pattern. The fact that the tire is heavier is not the reason. As long as you stay with a moderate All Terrain tire the difference is too small to notice.

 

Don't forget they make an LT version of the tire. You can look at same exact sizes except one may be an LT version (higher ply rating) and that could affect the rolling resistance which would affect mpg.

 

I'm not sure about exact MPG difference but tire/wheel weight definitely affects the performance. I noticed a slight difference when I went from the stock 24lb wheels to SCS F5s (19lb.) It didn't make the truck a race car or anything but the acceleration is improved.

 

Just saying but I went from 265/70R16 (stock OR) to 285/75R16 E load tires (33s) and according to old school math I get slightly better MPG

Regards to performance the bigger heavier tires make it sluggish off the line

 

Thanks, I was literally reading that article just now, and my fear was that I had read somewhere that each pound of unsprung weight was equivalent to 7-10 pounds of sprung weight, but 3 pounds sounds more reasonable if true. Thread pattern also has a huge effect in it.

 

265/70/17 Toyo open country at2 SL tires are like 38 pounds. I have them on my TRD pro Sema wheels and the combo is lighter than my factory set. I didn't notice any hit on mileage.

 

beautiful wheel

 

https://www.youtube.com/watch?v=a2Cz-Axvl9w

 

Thanks! I love em!

 

Just my own experience with my Mustang. I went to Enkei RPF1s and some lighter/summer tires for around an 8-10lb savings per corner and I definitely noticed the difference. My car could spin the tires without me even trying so I had to learn to be a little easier on the gas.

Now that had a lot more torque/hp than our trucks though not sure how our trucks would react though.