pizza cutters...General Grabber ATx

[Blueaz]

Airing down to a psi in the low 20s from high 30s or 40s makes plenty of difference and gives plenty of benefit. In addition to increased traction, it just plain makes the ride more comfortable. If you're stuck in deep sand or gravel or trying to crawl over rock obstacles, then airing down all the way to single digits might be needed but I wouldn't advise driving for miles and miles over multiple days like that. Our off roading in Arizona can have you out for days at a time covering a hundred miles with lots of sections near highway speeds. I haven't aired down below about 18-20 psi in years. If my tires are spinning I just break out the winch or the maxtrax.

 

[ktm525]

Depends on the tire width. At 20 psi, my 255/60R19 deflect quite a bit, enough that I'm not super keen try to go lower.

I guess it depends on the tire and how robust the sidewall is, wise choice without bead locks. In the video dropping to 20psi didn't increase tread contact patch much. When people say off-road I automatically default to a scenario where you are in 4 Lo not driving around off the pavement. Wouldn't bother airing down at all in that scenario.

 

[ftillier]

This past weekend I aired down, and it made a noticeable difference in comfort on the trail I was driving. There were times I was in 4-Lo, but mostly because it made throttle modulation easier not because I was climbing anything particularly steep and needed the extra torque.

 

[f1racer328]

I’ve had good luck at 20 psi and this is my first off road capable vehicle. Never had anything else to compare it to.

I am going to try 15 psi the next time I’m off roading.

Our off roading in Arizona can have you out for days at a time covering a hundred miles with lots of sections near highway speeds.

Also being in AZ I agree with this. A lot of our trails are super mild but just washboarded roads that feel great at 20 psi compared to 40

 

[Blueaz]

I’ve had good luck at 20 psi and this is my first off road capable vehicle. Never had anything else to compare it to.

I am going to try 15 psi the next time I’m off roading.


Also being in AZ I agree with this. A lot of our trails are super mild but just washboarded roads that feel great at 20 psi compared to 40

Totally agree - a 20 psi difference is a game changer on the miles of washboards up to Crown King!

 

[CRYA]

Hi all, reviving this as I’m due for new tires, like TODAY, and am definitely going interested in switching from 265/65 to the 255/70 “skinny”.

Do we have any confirmation that they’ll fit, or mostly fit? Looking at the new KO3 in LT. TiA!

 

[mm3846]

Mostly fit. I’m running 255/65-19 which is the same height. I think 1” lift? Still rubs here and there but nbd.

 

[ftillier]

Anyone running 18's consider the 245/70-18 KO3?

 

[greiswig]

I’ve got Cooper 275/70R18s on mine, with some trimming.

Anyone running 18's consider the 245/70-18 KO3?

 

[m_lars]

My understanding has always been that the reason you get LT tires is so that the stronger sidewalls allows you to run them deflated safer longer... But I agree -- LT tires property inflated for road use don't do much for ride quality.

It looks to me like the 255 is an "XL" rated tire rather than LT, no ? I'm no expert, but I thought XL was more of a heavy-duty passenger car tire rating that a C/D/E rated LT tires. May not have the same sidewall thickness if you're going offroad, etc.

I've always assumed that XLs are passenger car tires with an extra belt or extra material somewhere to allow them to carry a heavier load, but I never considered them suitable for an off road tire for a heavy truck.

I've always assumed LTs and Load Range E are best for heavy trucks like the Land Rover Discovery/LR4. This is based on how I use my truck, which is for every day road use as well as pretty heavy off road use.

I'm running Nitto Ridge Grapplers size LT275/65/18. On my truck I have the load range E1, load index 123 tires. The load range E1 means 10-ply rating with max load carrying capacity at 80 psi (80 psi is also the max pressure). The load index 123 equates to 3417 lbs per tire. These tires weigh 57 lbs each, tread depth is 16/32" (or 1/2"), and they are speed rated up to 100 mph. Cost is $323 per tire.

My same size tires are also available in XL rating. Load range XL means 4-ply rating with max load carrying capacity at 42 psi (50 psi is the max pressure). The load index drops to 116 or 2756 lbs per tire. The tires weigh 46 lbs each, tread depth is 13/32", and they are speed rated up to 118 mph. Cost is $289 per tire.

My assumption that XL tires are passenger car tires is obviously wrong...who is going to put 275/65/18 Nitto Ridge Grapplers on their passenger car? But looking at the ratings, I would expect that they are not as tough of a tire as the LT version. My main concern is sidewall punctures on sharp rocks. I'd love to lose 11 lbs per tire, save some money, and have the comfort zone of a higher speed rating (although I rarely hit 100), but I think I'd see off road punctures a lot easier than with the LTs.

Oh, and laughing at the "265 are pizza cutters?" comment. 235s are pizza cutters!

Boy, for a vehicle this heavy, I wouldn't consider not using an LT tire if I'm going to be doing anything trail-wise. I look at it this way: at some point on a difficult trail, a fair fraction of the vehicle weight is going to be on one or two of the tires, not spread across all four. And if those tires are sitting on sharp rocks, I want the extra sidewall support and protection the LT gets me. I'll let the suspension soak up the bumps for comfort, not the tire.

Sure. You may have different terrain in Oregon. Here in CO, I went with LTs mainly to provide some additional protection from all the sharp rocks we have...

It’s a common misconception that E rated tires have a “stronger” sidewall. They don’t. They have more layers in the sidewall to handle higher pressure and therefore a higher weight carrying capacity, but this does not translate to a more puncture resistant sidewall. Jeep guys who are rock crawl are not running E rated tires, but they are running tires known for sidewall strength in terms of puncture resistance. XL rating is more than sufficient to handle the GVWR of an LR3/LR4 on 3 wheels, will ride better (on or off road) and a true off road tire will hold up better than any standard E rated tire.