Help choosing new tires

[roaniecowpony]

My experience is that the moment arm increase of a larger tire has more to do with the decrease in acceleration and reduction in braking than any weight increase.

Next time you have your large tire equipped Jeep jacked and securely on stands and chocked, Put it in gear and accelerate the tires up to highway speeds and then apply the brakes. They accelerate and decelerate very quickly. You can almost instantly stop the tire rotation with fairly light brake pedal effort.

Diameter, tread pattern are the big effects on acceleration/braking, and fuel economy, IMO.

I believe a street pattern tread would clearly get much better fuel economy than a mud tread, all other things being equal. Anyone that has switched to mud tires clearly knows this.

Sponsored

 

[roaniecowpony]

A noisy tire is a fuel hungry tire. Noise takes energy to produce.

 

[Grey24Rubi]

A noisy tire is a fuel hungry tire. Noise takes energy to produce.

I'm sure you're right but with all due respect if anyone buys a Jeep Wrangler and even thinks about fuel economy in the slightest way, IMHO, they bought the wrong vehicle.

My 24 JLUR came with 488's and 33's ditched the factory 33's for 37's before the ink was dry on the check so I didn't hardly drive it much with the stock tires but I drove it enough to tell you, as you can imagine, there was a noticeable difference between the two in just about everyway. Oddly enough one of the areas that surprised me was acceleration from a dead stop but I'm sure having 488's helped lesson that.

Easily the most noticeable difference was the amount of brake pedal effort. The added rotational weight definitely requires you to step harder on the brake pedal then did the factory tires and wheels that weighed quite a bit less.

When it comes to wheelin though I will gladly take the disadvantages of the added rotational weight of the 37's.

 

[c20040215]

A noisy tire is a fuel hungry tire. Noise takes energy to produce.

Well, I have different take on this.
Yes. Noise takes energy to product, but sometimes "quiet tire" doesnt mean it generate less noise. It uses the tread pattern to create different frequencies noise and cancel each other out. Some do better than other.

My noise cancellation earbuds take energy to quiet things down for my ears.

But yes. Loud MT is never good for MPG.

 

[grimmjeeper]

I'm sure you're right but with all due respect if anyone buys a Jeep Wrangler and even thinks about fuel economy in the slightest way, IMHO, they bought the wrong vehicle.

My 24 JLUR came with 488's and 33's ditched the factory 33's for 37's before the ink was dry on the check so I didn't hardly drive it much with the stock tires but I drove it enough to tell you, as you can imagine, there was a noticeable difference between the two in just about everyway. Oddly enough one of the areas that surprised me was acceleration from a dead stop but I'm sure having 488's helped lesson that.

Easily the most noticeable difference was the amount of brake pedal effort. The added rotational weight definitely requires you to step harder on the brake pedal then did the factory tires and wheels that weighed quite a bit less.

When it comes to wheelin though I will gladly take the disadvantages of the added rotational weight of the 37's.

It's not the extra weight. It's the increase in leverage from the bigger tire fighting against the brakes.

 

[sherpaJL]

I'm sure you're right but with all due respect if anyone buys a Jeep Wrangler and even thinks about fuel economy in the slightest way, IMHO, they bought the wrong vehicle.

winner, winner, time for dinner..

 

[Chrisazm]

You are completely ignoring the fact that you're not just changing the rotational velocity of the tire. The tire is on the ground and is being driven to change the linear velocity of the vehicle.

That's where the diameter of the tire really factors in. The diameter of the tire directly impacts the force applied for vehicle acceleration. It's why you change axle gears to match tire diameter changes. The transmission can compensate a little if you're close. And modern transmissions are better than ever. But they can only help so much.

Tire weight is just minor parasitic drag which is why it's such a small factor in actual vehicle performance.

Yes I didn’t mention how the tire size affects acceleration based on gearing etc. but with a 392 and 456 gearing going from 35 to 37 doesn’t change much there. Once again my main point is that I do notice the difference in the tire size when driving and the MPG between 35s and 37s for me is the same. I’m not sure what you are disagreeing with here because they are my observations. Have a good one!

 

[Ratbert]

Well I landed on the BBATs and ordered them from Discount Tire last night to be installed August 9th. They were able to actually find me a price match even better than I could find which saved a little bit of money on top of the current $100 rebate on Mickey Thompson tires. I am going to be starting the axle swap on the 8th so I will have all tires pulled which will make it nice and easy.

Hopefully you mentioned that Costco doesn't charge for installation to get that taken off the bill.

 

[jdhunt0]

I have been very happy with my Maxxis RAZR MTs. 50k miles and still going.

 

[roaniecowpony]

I'm sure you're right but with all due respect if anyone buys a Jeep Wrangler and even thinks about fuel economy in the slightest way, IMHO, they bought the wrong vehicle.

....and still there are many threads on this forum about how much fuel economy they are getting.

 

[3TV]

Here are the new Toyo Open Country RT Trail 35x12.50R17 tires on my wife's daily driver. I really like this tread pattern over the Nitto Ridge Grappler I was thinking about getting. You can feel noticeably less rolling resistance and they are a lot quieter than the Nitto Trail Grapplers they replaced. Maybe the Gladiator with a 3.6 won't get worse gas mileage than my 392 now.

 

[Ratbert]

I have been very happy with my Maxxis RAZR MTs. 50k miles and still going.

Is it just me, or were those overinflated?

 

[jdhunt0]

Is it just me, or were those overinflated?

Probably a little, but if I run under 30psi I get DW when I hit a big pothole.

 

[Ratbert]

Probably a little, but if I run under 30psi I get DW when I hit a big pothole.

Oh, so there's something fundamentally wrong with your rig that gets masked by that pressure.

Note that I've got 49k miles on my 37" KO2s that I've been running at 37 PSI from day one and they've worn extremely evenly across the face. Mine (a built diesel) is pretty damn heavy though.

 

[JesseT]

My analysis paralysis has moved on from the lift part of my build to now what tire to choose. Looking at 37s. My driving is a high majority on road with the occasional offroad journey.

Is there any reason I shouldn't go with the ko2s? Looking at going with a load range of D. The C is significantly cheaper, but my understanding is people feel they are too "squishy" for 37s.

The Baja Boss is a great looking tire as well but its 10 lbs heavier.

Ive got 33" Toyo AT3 on now and theyre great on road but honestly I havent been super impressed with them offroad.

Any other choices I should be strongly considering?

I went from stock KO2s (285/70r17) to BajaBoss ATs (255/85r17). I can't speak extensively on the KO2s because I only ran them for about 10k mi, but I did change them out at that point because of how unimpressed I was with them. They performed very well on sand, dirt and scree, decently on snow, and they didn't give me any issues on cool, dry pavement (which we get for like 17 days out of the year where I live). On hot pavement they would whine when braking downhill, and I found their performance on wet pavement to be...concerning. My wife, who is less attuned to this sort of thing than I am (but is accustomed to the IMO extremely impressive Michelin CrossClimate2s on her Subie), made unsolicited comments on how sketchy my tires were in the rain on multiple separate occasions of borrowing my vehicle.

It's not exactly apples to apples because I went from a 285 to a 255, but the Baja Boss ATs are fantastic on wet pavement and either equal or outperform the KO2s on every surface I've had them on. I have not driven in the snow with them yet though so I can't speak to that.

If I had to change tires again and I couldn't get the Baja Bosses, the KO2s would be absolute last on my list among the "premium" brands.

That said, lots of people seem to love them so...idk. Maybe I just got a bunk set. Maybe they don't agree with the road compounds that we use in the Pacific Northwest and are perfectly fine in other regions of the country (though I do see lots of sets in my area too). Maybe if I off roaded more and drove in the rain less the places where they fall short wouldn't have been so glaring. But every now and then I will run across someone else who had a similar experience to me and is equally baffled by their popularity.

Sponsored