Is an 18" wheel better than a 15" wheel?

[TerryMason]

I've been looking around for some new wheels, and I've seen plenty of Jeep take offs - the one I've got my eye on now is a 2018 Sahara set with less than 300 miles. I've noticed that all the new Jeeps have 17 and 18 inch wheels from the factory. My old TJ came with 15s.

Is this just a cosmetic thing, or are larger wheels in any way better than smaller? I had always thought that a smaller wheel meant more rubber, and a better offroad experience.

 

[JPNinPA]

Well here is my 2cents.

It all depends on what you want to do with the jeep and how tall a tire you want to run. Lots of people set up for 35 in tires so on 15 that's 10 in of sidewall vs 8.5 in sidewall on 18's and 7.5 on 20's. On 33 in tires 18 in rim leaves 7 in of sidewall.

Off-roading you will likely air down. If you have too little sidewall there will not be enough tire plus air to keep the wheel from being damaged crawling over rocks, stumps and trees. How much is enough? Idk. But 35 in and above there should be enough sidewall.
I'd also think, though I have no data, just my suspicion that the tire may slip off the rim easier or pop a bead easier with a larger diameter wheel. I say that because the bead of the tire is made to stretch a bit. If that is constant larger diameters stretch more thus are more likely to pop off the bead. Esp when aired down.

The benefit to larger on the highway is less sway from the sidewall height. Less wander or better steering response.




Regards,
JPNinPA

Sent using TapTalk

 

[TerryMason]

Thanks for the reply, that makes sense. I had a feeling that more sidewall would generally be a better thing offroading.