Fuel economy with 35 inch tires

[blownout1500]

What tires and lift are you running and what area of the country are you in? Thx

Ready lift 2” level w/uca 35x12.5r18 ko2 sf Bay Area

 

[Bleda2002]

so me too here, but I think whats happening is this:

1) I think these tires weigh 55ish lbs each if I'm remembering correctly, thats pretty heavy. The other trucks with P rated tires are like 38 I think?

2) The tread. its pretty aggressive. And while weight is probably the number one factor, a highway tire has alot less rolling resistance vs an aggressive all terrain like these.

So these two things hurt the mileage, but I think if you switched to a 34-35 that you wouldnt really notice as much as a hit as you normally do on other trucks that switch from lighter P rated tires that they only put on there for mpg reasons.

12 does seem pretty low, im in the 14ish range mixed. But I dont much "city" driving per say. Can barely average 16 on the hwy though at all lol. more like 15.

I'm coming from a ecoboost truck that averaged 19ish, so I'm super thrilled about it. I used to daily drive a 6.0 2500HD gas truck on 37s that would average about 12 not ever going over 65, so having a stock half ton get anywhere near that is a bit of a pisser.

Surprisingly its actually the tread and actual size of the tire that has the biggest effect on MPG. The weight does matter, but mostly its because its moved farther out on the tread. They did an expirement on off road magazine, and losing 28 pounds a corner increased mpg by about .6 if i remember right, where as the tread alone was responsible for a much larger chunk.

The extra weight matters on acceleration and stopping, but once you're moving and cruising its more or less a non-factor as physics has it at a near constant energy state and the only real drain is air resistance and rolling resistance from the tread.

 

[SilverSurfer15]

Makes sense. I know my all terrain Mpg has always been noticeably better than my mud terrain mpg on the same trucks in the past. And same with cars, an all season tire will get more mpg than a performance tire that’s constantly trying to grip the road harder. But that may also be the difference in softer vs harder rubber.

Either way, the least rolling resistance = the most mpg. And I don’t think the stock duratraca are good for that. I would think the Toyo at2 or other true all terrain would do a bit better?

 

[TimmyG]

Very similar experience with 35x12.5’s and 3.92 gears. Power loss was barely noticeable. I’m getting about 10 city / 18 highway.

Here’s a screenshot from a 2hr all-freeway trip today:

View attachment 8365

Do you remember what speed you were running on this trip? Thanks for replying to all my questions. Gives me hope for 18 mpg hwy with similar mods lol

 

[blownout1500]

Do you remember what speed you were running on this trip? Thanks for replying to all my questions. Gives me hope for 18 mpg hwy with similar mods lol

Let’s just say fast lane speeds, but of the adult variety

Do you remember what speed you were running on this trip? Thanks for replying to all my questions. Gives me hope for 18 mpg hwy with similar mods lol

Let’s just say fast lane speeds lol

 

[TimmyG]

Let’s just say fast lane speeds, but of the adult variety


Let’s just say fast lane speeds lol

in that case I'm surprised it got good mpg

 

[blownout1500]

in that case I'm surprised it got good mpg

Speedo calibration might be throwing things off(?). Oh well... definitely plenty of smiles per gallon.

 

[TimmyG]

Speedo calibration might be throwing things off(?). Oh well... definitely plenty of smiles per gallon.

Worth it

 

[Bredtodo]

I’m getting 13 mpg now with a 6” lift, and 35’s. It dropped 3 mpg once the tires were added.

Oh well, keep the Middle East happy.

 

[Wheeler]

What psi u are running on 35s.
I pumped up to 55 I can hold 8th gear on Freeway. Getting 17+ cruising at 65. If you keep tire size and miles traveled it is better than showing on EVIC. AT 36 PSI never shifted to 8th gear unless speed up to 70band then slow down and cruise at 65.

 

[pber1]

Cuttently getting 12-13 city and 17-18 highway in the SF Bay Area as well. I’m on a 6in lift with 35in Toyo tires.

 

[TimmyG]

Cuttently getting 12-13 city and 17-18 highway in the SF Bay Area as well. I’m on a 6in lift with 35in Toyo tires.

This is awesome. What gears, 3.21 or 3.92? What tires? And what speed do you cruise on hwy? Thanks

 

[pber1]

This is awesome. What gears, 3.21 or 3.92? What tires? And what speed do you cruise on hwy? Thanks

I have the 3.21 gears and cruise anywhere from 65-70, 68 is my comfort zone. I’m originally from the Central Valley so I go every weekend and at 65 I can get 19mpg in the valley.

 

[TimmyG]

I have the 3.21 gears and cruise anywhere from 65-70, 68 is my comfort zone. I’m originally from the Central Valley so I go every weekend and at 65 I can get 19mpg in the valley.

Nice! Do you notice any gear hunting between 7-8 on inclines? Also, your sig doesn't say which Open Country tires. I was wondering which (I'm taking tire weight and tread pattern into account). Thanks

 

[pber1]

Nice! Do you notice any gear hunting between 7-8 on inclines? Also, your sig doesn't say which Open Country tires. I was wondering which (I'm taking tire weight and tread pattern into account). Thanks

Haven’t noticed it and I’ve had them on since November! I’ll make sure to specify in my signature but they’re the Open Country R/T

 

[TimmyG]

Haven’t noticed it and I’ve had them on since November! I’ll make sure to specify in my signature but they’re the Open Country R/T

Sounds like you are very satisfied with the setup! Just saw your profile pic of truck. Looks badass, love the white. Did you notice a big difference around town in acceleration with the 35s? Thanks for answering all my q's

 

[ksn240]

Haven’t noticed it and I’ve had them on since November! I’ll make sure to specify in my signature but they’re the Open Country R/T

Good to hear. I have the 3.21s also and so I have been leary of going with 35s. Think I am going to do it anyway along with a 6" lift. It will be a year or so before I do that though. Have a few other projects to do before then. Just rocking a leveling kit for now with 34s.

 

[pber1]

Sounds like you are very satisfied with the setup! Just saw your profile pic of truck. Looks badass, love the white. Did you notice a big difference around town in acceleration with the 35s? Thanks for answering all my q's

Thanks man! Not really but you can feel more it when you’re turning from a complete stop!

 

[pber1]

Good to hear. I have the 3.21s also and so I have been leary of going with 35s. Think I am going to do it anyway along with a 6" lift. It will be a year or so before I do that though. Have a few other projects to do before then. Just rocking a leveling kit for now with 34s.

Good stuff bro! I didn’t wanna go that high to begin with but I’m beyond happy with the set up now!

 

[ksn240]

Good stuff bro! I didn’t wanna go that high to begin with but I’m beyond happy with the set up now!

I originally wasn't planning for it when I bought the truck so I didn't care about the gears. I figured a level and 34s would be all I did, but now I am wanting bigger.