TV Tires

Stick with stock size if you can. OS tires will throw your speedometer off and could possibly mess up your enissions.

donn0128 wrote:
Stick with stock size if you can. OS tires will throw your speedometer off and could possibly mess up your enissions.

I don't see how increasing the width of the tire will impact the MPH.

It wont hurt the emmisions but it will throw the speedo off about 5 MPH and worse, it will effect where the power is.
FWIW, I have gone to the same size tire and unless you have added power, I would not make that big of a change.

ugh wrote:

donn0128 wrote:
Stick with stock size if you can. OS tires will throw your speedometer off and could possibly mess up your enissions.

I don't see how increasing the width of the tire will impact the MPH.

It's an aspect ratio thing. The height is 70% of the width so a wider tire is also taller given the same aspect ratio.

Olbeachcomber wrote:
Hi everybody. My tow vehicle is a 2012 Dodge Ram 2500, 2wd. It is ready for new tires, and currently has 245/70r17 tires on it. I have found a great deal on a set of 285/70r17 tires, but am unsure as to what the pros / cons of this tire. The tire guy tells me there is no problem going to this size tire, but then again, he is trying to sell tires.
Has anyone else here done this, and if so, are there any concerns?

The only difference between your stock tires and the tires that you are thinking off is the width of the tire across the thread. Its a wider tire. I don't see that as a problem except the tire could rub the frame or something when you turn. Most tire stores have a database that list other size that will fit fine. If the sales man says it will be fine, then it may be fine. Try it and make sure they will take it back if rubs something.

I think the 285's are about 2" taller, and less than 1" wider.

The only difference between your stock tires and the tires that you are thinking off is the width of the tire across the thread. Its a wider tire.

That is not the only thing larger. Tirerack offers some details on understanding tire sizes.

OP, the proposed tires are 7.2% larger. So at any calibrated/displayed vehicle speed, you will be going 7.2% faster. At 65mph indicated, you will be traveling at 69.5mph.

You will be losing torque. The math works the same as a percentage, so you are down 7.2% wheel torque at the same engine speed/gear. If you have a gas engine, you are that much farther out of the powerband when cruising. And larger tires tend to weigh more. Higher unsprung/rotational weight means it takes more power to turn or stop turning. I would expect slower acceleration, more fuel used, and increased brake wear.

If all that is acceptable, go for it! Personally, I'd stick to stock size.

ugh wrote:

Olbeachcomber wrote:
Hi everybody. My tow vehicle is a 2012 Dodge Ram 2500, 2wd. It is ready for new tires, and currently has 245/70r17 tires on it. I have found a great deal on a set of 285/70r17 tires, but am unsure as to what the pros / cons of this tire. The tire guy tells me there is no problem going to this size tire, but then again, he is trying to sell tires.
Has anyone else here done this, and if so, are there any concerns?

The only difference between your stock tires and the tires that you are thinking off is the width of the tire across the thread. Its a wider tire. I don't see that as a problem except the tire could rub the frame or something when you turn. Most tire stores have a database that list other size that will fit fine. If the sales man says it will be fine, then it may be fine. Try it and make sure they will take it back if rubs something.

Hey ugh, start reading before you throw out bad info. The 285 is a couple inches taller than the 245..... And wider.
To the OP, that size tire will work fine. You'll lose a bit of power to the ground spinning the bigger tires. If you have a gasser and tow heavy, keep the pizza cutters, but full size HD trucks just look better with tires that fill out the wheel wells a little.
If you have a diesel, doubt you'll notice much/any power loss.
Your speedo will be off a little at hwy speeds but possibly only a couple mph or none at all. I've noticed all the new work trucks I've driven with little tires the last few years are actually calibrated for the more popular sizes offered and speedo actually reads a little fast with the small OE tires. My last F250 came with 245s. When I got 285s it actually corrected the speedo.
Also Ram has 2500s with bigger tires than that sitting on the lot. No issues with rubbing or being too big.
And whoever said it will affect the enissions?? Huh? I'm confident a new set of tires has nothing to do with emissions.

Edit, just read it's a 2wd. What I said still holds true except I'm not certain about tire clearance in front.
Just tell the tire guy to mount one up and then you can see how it fits.

Thank you all for the replies. I think I am going to go ahead and roll the dice and go with the 285's. From what I gathered from here and other forums, I don't think there will be much of an issue.