Tires affecting MPG

[Tjsieberg]

My 1500 with the 5.7 Hemi is about ready for new tires. I bought the truck with 35/13.5R18 tires that are fairly aggressive. With these tires I have only been averaging 15.4 mpg on the highway. I was thinking about buying new 20 x 9 rims for it and getting a more stock size tire such as the 275/60R20 that came on the truck from the factory. I would still like a fairly aggressive tire but nothing crazy. How much will these smaller tires improve my fuel economy? I drive the truck mostly on the highway and don't pull trailers with it very often. Is it even worth the time and money to find new rims or will I just be wasting my time and money? Any recommendations for tires or rims?

Thanks, Trevor

 

[nekkidhillbilly]

i usually avg 18 with the stockers thats mixed driving.

 

[ThunderMug95]

Stock sizes will yield noticeable mpg over the larger tires. Another consideration…are you lifted? It could yield tiny wheels/tires in a huge open wheelwell syndrome.

 

[LouM]

Why 20's?
18's can easily be the same height.
265/70r18 are 32.6" in diameter
And the taller sidewall will usually result in a better ride and traction

And 18's cost a lot less normally.

 

[RamDiver]

Why 20's?
18's can easily be the same height.
265/70r18 are 32.6" in diameter
And the taller sidewall will usually result in a better ride and traction

And 18's cost a lot less normally.

And if using them in snow or offroad, narrower tires with more sidewall are a big advantage.
I think my winter tires are 255/75-17 or close to that.

Update; My BFGs are 245/70R17 and they perform fantastic in the snow & crud.

I have summer & winter wheels because of the local conditions here. Sometimes it takes 36 hours before they plow in my area, the joy of rural life.

I don't care, it makes owning a truck with BFG KO2's that much more fun.
.

 

[Burla]

I didnt like the 20's on my 1500 and went with 18's, same sentiment above with the larger side walls and how trucks are supposed to look and function, you don't own a chevy I hear those guys love thin tires with no tread.

If you do opt for your plan, slam it. I have warmed over the years for this on rams, but for me I prefer a lifted truck. your mpg gains would be noticeable, 1-2 mpg. BFG tires white label out are pure truck ****, if that aint your thing consider a drop so the lack of air moving under truck will please you at the pump. Get creative with air damns you will likely gain even more. Get a michelin defender tires or some smooth tire. You are in Minn and those BFG's will hunt in the snow. You have more decisions then just mpg's looks like.

 

[Daw14]

Tire weight can have a large impact on mileage, just another thing to keep in mind.

 

[CanRebel]

My Rebel come with 18's and I switched to 20's.

As few others above mentioned. Putting 18's will help. If you search in your local area or even some dealers.
You might find some new and/or used 18's that someone switched.

 

[ThunderMug95]

Yeah if you look at local forums like Craigslist or Marketplace, you can find take-offs etc. i picked up a set of 20x9 Ram Sport 5 spokes a couple years ago for $300 with bald tires…Just because. Twice in the last month have seen Gen 5 Rebel wheels on Marketplace. Ram switching to 6 lug was a dirty trick…

 

[RamDiver]

I found OEM steel 17" 5-bolt take-off rims from my dealer for $69 Canadian, what's that, $29 US?

I wish my Warlock would fit the 18" 6-bolt rims, then I could have used tires from my previous truck and saved a pile of cash. My local guy found 18" rims for $110 Canadian.

The point is, regardless of the size, ask the stealership, you never know without asking and that much is free.