Tire Question

[GoBlue24]

Currently have the stock/Night edition 275/55R20's with all-seasons. Looking to get a snow-tire but keep the current wheels. Any issue with going to a 275/65/20 size, for example?

 

[tron67j]

The new tire is going to be about 2 inches taller, can your truck clear that? Not the best way, but you could measure from top of current tire at full left and full right turn plus straight and see if anything is 1 inch or less from top of tire. The truck bouncing could cause any close clearance to disappear.

 

[Badger 13]

I have that size, LT275/65R20 on my stock wheels, (2013) with no issues whatsoever.

 

[mikeru]

Yeah that tire size should be fine on your 5th gen. If you have air suspension you will probably get some rubbing with suspension in entry/exit mode and turn the wheel fully. You're essentially going from a 32" tire to a 34" tire. Just remember that your speedometer will be affected. You will be going almost 5 mph faster than the speedo says at 65 mph.

I have that size, LT275/65R20 on my stock wheels, (2013) with no issues whatsoever.

OP is asking about a 5th gen. What works for your 4th gen may not necessarily work on a 5th gen.

 

[BobinTX]

On my '21 RAM 1500 Laramie 4x4 Crew Cab, I went from stock 275/55/20 tires to 295/65/20 without issue, with a caveat. Before the tire upgrade I installed Bilstein 5100 struts on the frontend to level the truck but left the rear OEM shocks as is. However, now when I lock the steering wheel hard left or right, as in getting in or out of a parking spot, I notice very slight rubbing. Not really an issue, but I plan to physically trim some of the rubber/plastic underbody splash guards or other pieces that make contact with the larger tires when fully turned in either direction. If you stick with the more narrow 275 tires, you probably wouldn't have that problem.

Also, after upgrading the tires, I took my truck to the local RAM dealer and paid them $145 to recalibrate the speedometer for the larger tires. After the recalibration I checked the speed against the Waze App on my phone and the two are perfectly in sync with each other.

 

[RamDiver]

Currently have the stock/Night edition 275/55R20's with all-seasons. Looking to get a snow-tire but keep the current wheels. Any issue with going to a 275/65/20 size, for example?

to Ram Forum.


You can make virtual comparisons to different tire sizes without leaving the comfort of your home. Find the tire you prefer on the manufacturer's site to confirm the size is available, and plug the numbers into a calculator like the following URL.
Be sure to select the Tire Comparison tab.

Tire Size Calculator

The best tire size calculator. Use our tire size calculator to find tire size specs and suggested tire sizes. Then check prices for all available tire sizes.

tiresize.com

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[Gary Fields]

Supposedly your speedometer/odometer will compensate for the new tire size. It uses the GPS system and over about 100 miles will calculate the correct speed and distance from GPS and recalibrate your vehicle automatically. I read this but don't recall where. You may look into this or just see if it works. Find an empty interstate and see what 10 miles posts and your odometer show. At 60 mph it should take 10 minutes. Texans use 90 MPH and it takes them 7.5 minutes to avoid being a traffic hazard.

 

[graydon]

On my 2025 Laramie I went from 275/55x20 to 285/60x20 Toyos with no rubbing. They are 1.5 inches taller (33.5). They were the only 4 ply AT tires I could find in that size. They did cut my gas mileage by at least 1 mpg after calculating in the 5% difference in speed/distance.

 

[50BMG]

Currently have the stock/Night edition 275/55R20's with all-seasons. Looking to get a snow-tire but keep the current wheels. Any issue with going to a 275/65/20 size, for example?

I've used that same size tire on 3 stock/un-lifted 1500s in the past and my current 2" lifted Ram 1500 with no "real" issues to worry about.
I ran the even bigger 285/65/20's on my 2013 Ram and the only issue I had was a very slight rubbing on the lower A-Arm when the wheel was turned 100% to one side (can't remember which way it was, but I'm pretty sure it barely rubbed only on one side, but again, ONLY when like doing a U-turn and the wheel was at the extreme/stop on that one side. Not a big deal at all!).
All of the above on factory stock wheels.

But, after you go to the taller tires, your truck will tell you that you are now getting @ 7%-10% worse mileage which IS NOT TRUE! The issue is that the taller tires rotate @7%-10% less times/mile. So, your truck will be tricked into thinking you are using the same amount of gas at @ a 10% lower speed, which it isn't. Yes, your speedo is off a little bit too of course, but that's only a few MPH at "normal" driving speeds, a few more at highway+ speeds.

I think the dealer can adjust the ECU/speedo computer to accommodate for the larger diameter wheels, but I always try to avoid taking the truck to the dealer for such things. You may discover they will change "stuff" that you liked and didn't tel them to adjust in the first place.

 

[Ramfanski]

Also, if you get a much heavier tire, your acceleration may suffer some, especially from stopped.

This is a good example of when the gears in the rear end make a big difference.

 

[RamDiver]

Also, if you get a much heavier tire, your acceleration may suffer some, especially from stopped.

This is a good example of when the gears in the rear end make a big difference.

The acceleration with my 3.21 Hemi and 10-ply E-rated BFGs weighing in at just under 53 pounds each, isn't lacking, AFAIC.

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[Ramfanski]

The acceleration with my 3.21 Hemi and 10-ply E-rated BFGs weighing in at just under 53 pounds each, isn't lacking, AFAIC.

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lol, Hemi’s rock!

Put the same diameter tire that weighs 43 pounds, and you will see a big difference!

I have a 3.21 myself, but if I was going to run big mudders, I’d have gotten the 3.92. I like the mileage on the highway too much.

Enjoy the nice tires.

 

[RamDiver]

lol, Hemi’s rock!

Put the same diameter tire that weighs 43 pounds, and you will see a big difference!

I have a 3.21 myself, but if I was going to run big mudders, I’d have gotten the 3.92. I like the mileage on the highway too much.

Enjoy the nice tires.

I use 40-pound Michelin Defenders as summer tires every year. There may be a minuscule difference with the 'get up and go', but nothing too noticeable.

Ever since installing the Pedal Commander, the truck always feels like a rocket ship to me.

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[Ramfanski]

I use 40-pound Michelin Defenders as summer tires every year. There may be a minuscule difference with the 'get up and go', but nothing too noticeable.

Ever since installing the Pedal Commander, the truck always feels like a rocket ship to me.

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I had a pedal commander for my last truck. They do spice things up!

 

[50BMG]

Also, if you get a much heavier tire, your acceleration may suffer some, especially from stopped.

This is a good example of when the gears in the rear end make a big difference.

Put the same diameter tire that weighs 43 pounds, and you will see a big difference!

I have a 3.21 myself, but if I was going to run big mudders, I’d have gotten the 3.92. I like the mileage on the highway too much.

Have you actually confirmed this theory by doing some acceleration tests using the different sized/weights of tires with some certifiable type of device (like a GPS/G-force based type of track data instrument)?
"Seat of the pants" data doesn't count because IF there is any acceleration differences using what amounts to being "slightly heavier tires", the differences will be miniscule to say the least.
TALLER (or shorter) tires DO have an affect of changing the final drive ratio of the vehicle, but honestly, the "tire weight" differential itself has very little to do with any observed change in the vehicle's rate of acceleration (within reason of course; don't get silly and say you're going to use 400# tires compared to 40# ones).

By your logic then, heavier tires "should" get you better mileage on the highway too (assuming the heavier tire is the same diameter as the lighter ones OR the truck's ECU has been properly flashed to accommodate the larger tire diameter with the fewer rotations per mile they will make).
Certainly, the heavier tire would have more rotational inertia to keep the truck rolling along, once they have reached the desired highway speed, right? Harder to start rolling means harder to stop rolling too, right? Thus, better mileage on the highway!

I think you are overlooking the change of final drive ratio which comes from the use of larger diameter (and usually slightly heavier) tires and confusing it as being an affect which is accounted for by tire weight alone.

 

[Ramfanski]

Have you actually confirmed this theory by doing some acceleration tests using the different sized/weights of tires with some certifiable type of device (like a GPS/G-force based type of track data instrument)?
"Seat of the pants" data doesn't count because IF there is any acceleration differences using what amounts to being "slightly heavier tires", the differences will be miniscule to say the least.
TALLER (or shorter) tires DO have an affect of changing the final drive ratio of the vehicle, but honestly, the "tire weight" differential itself has very little to do with any observed change in the vehicle's rate of acceleration (within reason of course; don't get silly and say you're going to use 400# tires compared to 40# ones).

By your logic then, heavier tires "should" get you better mileage on the highway too (assuming the heavier tire is the same diameter as the lighter ones OR the truck's ECU has been properly flashed to accommodate the larger tire diameter with the fewer rotations per mile they will make).
Certainly, the heavier tire would have more rotational inertia to keep the truck rolling along, once they have reached the desired highway speed, right? Harder to start rolling means harder to stop rolling too, right? Thus, better mileage on the highway!

I think you are overlooking the change of final drive ratio which comes from the use of larger diameter (and usually slightly heavier) tires and confusing it as being an affect which is accounted for by tire weight alone.

No. I had a 2011 4.7 and put larger diameter and heavier Lt tires on it. Different transmission but made it downright dangerous turning with traffic coming. Terrible acceleration, especially 1st and second gear.

The mileage went to hell in city and on the highway. I did have my speedometer changed by the dealership so that it matched the actual speed.

I am not a scientist, nor would I spend as much time doing what you’re talking about. Of course my evidence is anecdotal. I would have no way of knowing whether the added height or mass had the most effect on acceleration or mileage. When I bought later and shorter stock tires, my mileage came back in my ex acceleration off the line was much improved. Like I said, anecdotal, and of course it counts. Just like all the lessons you have learned in life.