Towing with larger tires

[DOFF]

Hey everyone
Just picked up a ‘21 1500 big horn CC 6’4 bed 3.92 rear end. Drive it a couple days a week 60 miles to work. Have a travel trailer about 5,800lbs we tow up to the Eastern Sierras couple times a year with my previous 1500.
I want to do a level (most likely fox 2.0 or Bils 6112s for some light off-road fun) and a larger tire. I have the 275/65r18s (32.1x10.8) that came stock but the question is, how much MPG and “tow ability” would I be looking at losing with either a 285/75r17 or 285/70r18? Both about 33.9x11.2-ish. Both these seem light enough and fill out the wheel well without the “stuffed” look of 35s.
I’ve looked through so many threads my eyes are starting to hurt so figured I’d ask for some your experiences. I’m expecting to lose some, obviously, but any input would be greatly appreciated.

 

[myles]

If you have the hemi motor, maybe around 1-3 mpg with 10 ply tires and depending on how you drive.

edit: and for towability youre not really going to lose anything since you have the 3.92 gears

 

[Jeffjad]

I lost about 3mpg with 3" lift and E rated 35s. I don't even bother looking at mpg when towing my boat ...what's the point.

 

[myles]

I lost about 3mpg with 3" lift and E rated 35s. I don't even bother looking at mpg when towing my boat ...what's the point.

Seriously, thats one of the main reasons I switched to the ecodiesel. In my 15' gmc I was getting 6-8mpg on flat ground when towing my boat, now im getting 14 with the ecodiesel. Having to stop every 2.5 hours to get gas was a major PITA

 

[DOFF]

That’s kind of my issue. Is going from the 32s to a tall 33 going to kill MPG and ability to tow, making the switch pointless? Even tho it looks great haha

 

[myles]

That’s kind of my issue. Is going from the 32s to a tall 33 going to kill MPG and ability to tow, making the switch pointless? Even tho it looks great haha

mpg will definitely drop, how much depends on how you drive. If you drive like a grandpa, you'll prolly see a 1mpg drop, if you have a lead foot you'll probably see a 3mpg drop.

You wont even notice a difference in towing.

 

[Jeffjad]

That’s kind of my issue. Is going from the 32s to a tall 33 going to kill MPG and ability to tow, making the switch pointless? Even tho it looks great haha

Going from 32s to 33s will not make that big of a difference IF you stay stock with the suspension. If you add a level kit this will change your aerodynamics and hurt the mpg more so.

My truck tows way better with E rated tires.

 

[DOFF]

Thanks for the replies! I’ll post some pics soon with what I go with.

 

[Gitter]

Went from stock 32's to 10ply 34's and a level kit. Since you have a hemi with 3.92, tow ability is not an issue. You don't notice the bigger tires at all...even while towing.

You will see about a 2 MPG hit during normal daily driving, and more like a 1 to 1.5 MPG hit while towing. It's more than worth it:

 

[Richard320]

I'm pretty sure a 17" wheel will hit the brake calipers.

 

[MG99]

Hey everyone
Just picked up a ‘21 1500 big horn CC 6’4 bed 3.92 rear end. Drive it a couple days a week 60 miles to work. Have a travel trailer about 5,800lbs we tow up to the Eastern Sierras couple times a year with my previous 1500.
I want to do a level (most likely fox 2.0 or Bils 6112s for some light off-road fun) and a larger tire. I have the 275/65r18s (32.1x10.8) that came stock but the question is, how much MPG and “tow ability” would I be looking at losing with either a 285/75r17 or 285/70r18? Both about 33.9x11.2-ish. Both these seem light enough and fill out the wheel well without the “stuffed” look of 35s.
I’ve looked through so many threads my eyes are starting to hurt so figured I’d ask for some your experiences. I’m expecting to lose some, obviously, but any input would be greatly appreciated.

17’s are too small for the size of our brakes. Richard320 is correct.

 

[devildodge]

Yes. 18 inch wheel is the smallest you can use. And then some 18 inch wheels will still not clear the calipers

Do not level your truck if you plan to tow or haul.

 

[Gitter]

Do not level your truck if you plan to tow or haul.

Why is this?

 

[devildodge]

Trucks are designed with a rake. To keep the headlights pointed properly and to keep the weight ratio alive for weight on the front tires to steer and brake.

The level takes this away

Lift it properly with a front and rear lift to keep the rake.

But...i am anti-level. And in the I rarely use my truck market these days...everyone seems to need a level

 

[devildodge]

A 32 inch tire is about avg now a days. Going up one size will barely even be noticed by the truck

For instance...some 33 inch tires...are really only about 32 inch once they are mounted on the truck...most trucks now a days are pretty much designed for a 34 x 11 tire and most trucks will fit a 35 x 11.5 tire with no issue.

The 8 spd transmission has so many gears to pick from...it will compensate well when you decide to put the power to the ground.

 

[Gitter]

Yes, a level kit changes things, but it easy to adjust for this in an easy and safe manner.

Regardless if you tow, everyone should properly adjust their headlights after changing their suspension. That's a given. Add in airbags and there is no issue with the headlights while towing.

The only other adjustment I had to take was with the tow hitch and re adjusting the WDH. It will also readjust the weight so that it's properly distributed front and back.

 

[devildodge]

Well, most do not. And you can not use traditional wheel well measurements to adjust the WDH properly. You now have to use a CAT scale.

And you really should not need to install airbags with a properly set up truck.

But this is really opinion and off topic. So i will let it rest.

If someone does their due diligence then I suppose...but for someone using the truck daily...the level will get old

But, as I have learned in the past 3 years here...few people really use their truck anymore. And that is fine.

Was just offering a suggestion to the OP. If he is planning to tow and use 33 inch tires...there is no need to level and no need to add anything special to the truck if he stays within his limits.

 

[Peter 89]

Trucks are designed with a rake. To keep the headlights pointed properly and to keep the weight ratio alive for weight on the front tires to steer and brake.

The level takes this away

Lift it properly with a front and rear lift to keep the rake.

But...i am anti-level. And in the I rarely use my truck market these days...everyone seems to need a level

Get airlift bags and problem goes away