Upgrading to 18" truck tires

[Bayley]

I have a 2013 Ram 2500 CTD 4x4 that currently has 245/70/17 tires on it. I am thinking about moving up to the 275/70/18 tires. Has anyone done this and are there any major draw backs in doing this?
Thank you for your input!

[Bamaman11]

Bayley wrote:
UPDATE: Well I found some new take off 275/70/18E's from a 2015 Ram 2500 for a heck of a price on Craig's list.
I'm going to make the change but I now have another question:
A spare doesn't come in the deal so is it alright to use my current 17" spare? I called a tire dealer and they said it wouldn't be an issue if I didn't run it in 4 wheel drive.
anyone have any experience with this?
Thanks again for the help!!

Any truck with limited slip axles require the same diameter tires on the same axle. Two different diameter tires will damage the limited slip. If you were going to use a smaller spare, you'd have to move one of the front tires to the rear and mount the spare on the front. And you couldn't use the front wheel drive.

[bpounds]

clotus wrote:
Why can't you just get a new tire on your spare to match the diameter of the 18-inchers. The 17" wheel is not the problem, it is ultimately the sizing difference of tire's diameter. As long as they all stand the same height it would not be a problem regardless of where the "spare" was placed.

I think the point is to use an existing spare, and avoid purchasing a new tire that may never see any use. Same reason he wouldn't buy a 5th 18" wheel and just let it hang under the truck.

But if you wanted to do that, a 285/70-17" would be in the diameter ballpark.

[bigdon68]

Coach-man wrote:
Actually, "truck" tires are 19.5", not 18". Rickson tires will sell you the wheels, and a variety of 19.5 truck tires, as well as programing your computer to compansate for the larger tires. They claim 8 plus years on a set of tires!

I did the switch from 18" to 19'5" for my F350 SRW. Rickson Truck Wheel in Hunt Valley Maryland supplied me with 5 wheels and I installed the Michelin 245 70R XZE 19.5" tires - LR H. The diameter was so close to my 18" that it hardly effected my speedometer at all.
The ride is not bad and it really gives you a tire and wheel combination that will last. My tires and wheels are two years old and they look brand new.

bigdon68
Maryland

[Dtank]

clotus wrote:
Why can't you just get a new tire on your spare to match the diameter of the 18-inchers. The 17" wheel is not the problem, it is ultimately the sizing difference of tire's diameter. As long as they all stand the same height it would not be a problem regardless of where the "spare" was placed.

Way too logical..:B

BTW - (OP) you can compare tire sizes (diameter) in inches on various Internet sites.

Pick up a used 17" tire in the diameter you need to match the diameter of your new 18s"..;)

.

[clotus]

Why can't you just get a new tire on your spare to match the diameter of the 18-inchers. The 17" wheel is not the problem, it is ultimately the sizing difference of tire's diameter. As long as they all stand the same height it would not be a problem regardless of where the "spare" was placed.

[bpounds]

I kept my 17" spare. As said, it isn't good to run mismatched diameters with an LS differential. It will wear out the clutches, and possibly overheat the gear oil.

I figure worst case is having a flat on the rear, and having to move wheels around so that the spare ends up on the front. A hassle, but not a deal breaker to me.

I drove about 500 miles home on that 17" spare, and no issue. It was on the front.

[Me_Again]

If you have a limited slip rear end, it is an issue. And without locking/unlocking front hubs, I would not want to drive very far! Chris

[Bayley]

UPDATE: Well I found some new take off 275/70/18E's from a 2015 Ram 2500 for a heck of a price on Craig's list.
I'm going to make the change but I now have another question:
A spare doesn't come in the deal so is it alright to use my current 17" spare? I called a tire dealer and they said it wouldn't be an issue if I didn't run it in 4 wheel drive.
anyone have any experience with this?
Thanks again for the help!!

[wuhungsix]

I have a 2012 Ram 3500 SWR. Upgraded to 295/70-18. 3.73 rear end. No issues here.

[cutty72]

I think 17" will fall to the wayside far quicker than 16".
16s are just too popular with the off road crowd.

[N-Trouble]

Bamaman1 wrote:
I read recently how 17" tires may be going to be a thing of the past--with 18" tires preferable for trucks. You will still be able to get 17" tires, but just not so many brands and models.

I don't think you could go wrong if you need tires now, and if you can buy wheels for a fair price. There are a number of regional wheel reconditioners online that are buying all sizes and types of wheels from salvage yards.

I bought an 18" very wide wheel for my Lexus IS from a dealer in Atlanta for 1/4th the cost of a new one.

True. There will be less and less demand for 16/17" tires in the future as 18" have quickly become the norm wheel size on all new trucks.

[clotus]

I have a 08 Ram 2500 with 17". I carried a truck camper and needed added rear axle capacity. I went with the 285/70R-17 and could not be happier. If you are going to upgrade the 285s will fit nicely and are not too much taller. They should not affect your speedo too much, just check it with a GPS (I was about 2 mph off, hardly a difference). I like the Nitto Terra Grappler/Toyo Open County A/T for their tread life, traction, and carry capacity (3750 lbs). Just something to think about.

Head over to cumminsforum.com/forum tons of specific info for the Dodge crowd!!

[Bamaman11]

I read recently how 17" tires may be going to be a thing of the past--with 18" tires preferable for trucks. You will still be able to get 17" tires, but just not so many brands and models.

I don't think you could go wrong if you need tires now, and if you can buy wheels for a fair price. There are a number of regional wheel reconditioners online that are buying all sizes and types of wheels from salvage yards.

I bought an 18" very wide wheel for my Lexus IS from a dealer in Atlanta for 1/4th the cost of a new one.

[Bayley]

Thank you all for your input! I will check out the options!