Tire Pressure Theory-Compelling or Outlandish?

[Wolf Island Diver]

I just removed a set of 35" Goodyear Ultraterrains with 90k miles on them and I only rotated them once.

Yeah, I’m really impressed with how well the Gladiator handles big tires. The steering pump could be stronger (I’m holding off adding a booster until I get the recall fix). I also notice that crowned roads really require more steering compensation, but it drives really well and treats tires well.

One big caveat is this wasn’t the case on the stock Ecodiesel suspension. That was downright sketchy, but I think there was a shock valving issue addressed with a TSB. My AEV suspension is excellent.

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[WambliSka]

I don't try to fix problems that don't exist in my world. My tires ride the same from 37-43 psi on roads and highway (and yes there is THAT wide a range on PSIs when you live in the desert just from ambient and pavement temps) and the Mojave ride is better than I've ever gotten on ANY Jeep so I don't F with them as long as all 4 tires are in the same range within 1-2 psi. I might air down a little if I know the trail I'll be on has a lot of washboard areas (common in the SW especially in AZ) because it SEEMS like it dampens the rumble just a bit but with the Mojave I'm even getting away from that. That being said, I've always had a suspicion (not scientific, just a personal tingling of the spidey senses) that airing down too much just ultimately destroys the sidewalls of your tires and causes issue and potentially premature tire failure so I just don't.

 

[SargeDiesel]

Hey everyone-

Wanted to get some thoughts from the more experienced off-roaders and overlanders regarding a very curious approach to tire pressure that I just heard a week ago while wheeling up in Hollister Hills, CA. I was with several guys with multiple decades of experience both driving off road and, more importantly, running training courses in off-road driving and recovery for law enforcement, forest fire crews, and the military. What they told me was really surprising.

They all run their personal off-roading vehicles at very high psi for on-road and highway driving, and then air down to what almost everyone (on this forum and elsewhere) would consider on-road pressures for driving off road. So, for example: one guy driving his Tacoma on 35-inch BFG KO2s runs them at around 50 or 55 psi on the highway, then goes down to about 35 for off-roading. If he's on sand, he'll go down to 15 or 20 psi, and if he's doing serious rock crawling, he might go down to 25 or so.

For my E-rated 35x12.5x17 Toyo Open Country AT/iii's with a max psi rating of 65, he actually suggested I be running these at 50 or 55 for the highway, then airing them down to 35 for off road.

Suffice to say this runs counter to everything I've ever heard or read about tire pressure. But these weren't just any old dudes, they were pros. When I asked about uneven wear on an over-inflated tire, he brushed it off, saying that the steel belting inside the tire keeps the tread squared and in even contact with the road regardless (until you air way down). He said at the higher pressure on the road, you'll not only get better gas mileage, but have better handling and cornering and actually prolong the life of the tire. And he said that off-road, he believed that most people air down way too much, especially those with heavy loads.

I sort of gave things a go last week and just kept my tires at 35 psi while wheeling all day with them up in Hollister (on moderate trails, admittedly) and to be honest, I never felt like I was wanting for traction. But I don't have a ton of off-roading experience so I'm not sure I'm in a position to appreciate the nuances. Certainly, I'm aware of the benefits of airing down when rock-crawling (allowing the tire to squish and wrap around rocks and obstacles). So this all left me a bit stumped.

What are your thoughts? I'd be keen to know if anyone else approaches their tire pressure this way or if this just sounds crazy.

IMO... For the highway it's pretty simple, do the chalk test and it'll tell you exactly where you need to be. For off roading, I think it's a preference and ultimately depends on the terrain. As others have said, there's a huge difference between independent suspension and a solid axle.

 

[fourfa]

I'm wondering how my Toyo Open Country AT/iii compares to the old KO2s in this sense. My sense is the E rating comes from a thick sidewall, but just a guess, really.

I was talking about the original KO (not the current KO2/KO3). Those were the go-to "AT" tire for a long time before the AT category really existed as we think of it today. They were basically a relatively thin 80psi light truck carcass with a knobby tread. I had a set; I tore the sidewalls out on sharp rocks in Death Valley twice before I got wise and dumped them in like 2009

 

[Pickle_Bill]

Tread Lightly...air down!

 

[White Eagle]

If the tire doesn’t have some give when you push your foot against it, you’ll have a blowout the first trip into my ranch.

I love so called “professionals” as much as cops, tacticool, pipe smokers, and self proclaimed cognoscenti.

 

[Bandit’s Lair]

I love so called “professionals” as much as cops, tacticool, pipe smokers, and self proclaimed cognoscenti.

I was in LE for 20 years, I smoke Carter Hall on occasion, I have some Velcro, and I had to look up the last word. Love you too Bud.

 

[WambliSka]

I think like most things in the Jeep world... or just in the world... the answer is a strong "depends" and based on your personal use case and recognition of the hundreds, if not thousands of variables between our circumstances and others. My Jeep is very capable vehicle but HIGHLY unsuitable for some of the crap I see online. I respect it's limits and mine because ,as I've mentioned before, a off-road trail for me is just a delivery method to a destination, not the actual quest.

I'm never going to put myself in a position in which I need bead lockers desperately trying to crawl on tires with 2 lbs of air in them. I literally have zero taste for it. So if I can't make it with my reasonably capable vehicle and my excellent tires, without a lot of technical drama and 12 spotters, I'll find another way in.

Your mileage WILL vary...

 

[WambliSka]

I was in LE for 20 years, I smoke Carter Hall on occasion, I have some Velcro, and I had to look up the last word. Love you too Bud.

Oh hell, I actually restore classic pipes for a fun hobby... I'm a JM Boswell's man myself!

I think I can feel the love

 

[Janster]

I'm never going to put myself in a position in which I need bead lockers desperately trying to crawl on tires with 2 lbs of air in them. I literally have zero taste for it. So if I can't make it with my reasonably capable vehicle and my excellent tires, without a lot of technical drama and 12 spotters, I'll find another way in.

Your mileage WILL vary...

Aww…C’mon! I dare ya!! . Sit in the passenger seat with someone on the extreme rocks, it’s a bit of an adrenaline rush. If you’re driving…. .it’s both scary & exciting at the same time, especially when tires start coming off the ground.

We did our fair share of somewhat ‘extreme’ terrain…..beadlocks not needed. Custom roll cage that was used….twice. I miss those days…… when I was 20 years younger.

 

[WambliSka]

Aww…C’mon! I dare ya!! . Sit in the passenger seat with someone on the extreme rocks, it’s a bit of an adrenaline rush. If you’re driving…. .it’s both scary & exciting at the same time, especially when tires start coming off the ground.

We did our fair share of somewhat ‘extreme’ terrain…..beadlocks not needed. Custom roll cage that was used….twice. I miss those days…… when I was 20 years younger.

Oh, I still have tires in the air here and there. And shelf roads don’t scare me much. I’m just not a boulder hopper and I don’t tend to end up wheels up in my new truck when all I want to do is comfortably get to a serene spot and smoke a cigar with my wife or a couple of buddies at in solitude.

That’s why Jamborees and such give me the heebie-jeebies. The thought of sleeping among 200 drunken folks only so I can get into an all day traffic jam next day is NOT appealing at all to me. A campfire with wife and/or 2-3 buddies and a bottle of great Bourbon consumed in moderation is ideal.

 

[Bandit’s Lair]

Oh hell, I actually restore classic pipes for a fun hobby... I'm a JM Boswell's man myself!

I think I can feel the love

Im more into corn cobs these days. I did have a few good pipes but the cost outpaced me so I went cheaper and actually enjoy them a bit more. I sanded one out from a briar block many moons ago but have no idea where that one got to. Mostly a Carter Hall, Dunhill, and used to be McClelland guy myself, a little Orlik now and again if I could find it. The froggy ones, EMP, 965, and if I could find the old 3 nuns I’d be on it like stink on cow pies.

 

[WambliSka]

Im more into corn cobs these days. I did have a few good pipes but the cost outpaced me so I went cheaper and actually enjoy them a bit more. I sanded one out from a briar block many moons ago but have no idea where that one got to. Mostly a Carter Hall, Dunhill, and used to be McClelland guy myself, a little Orlik now and again if I could find it. The froggy ones, EMP, 965, and if I could find the old 3 nuns I’d be on it like stink on cow pies.

Not to derail but I've never managed to learn to smoke a Cob pipe the correct way. My son-in-law got me into pipes a while back (I've always been a cigar man) and like every new hobby I get into I will find the "rabbit hole". I found cleaning and restoration "How-To" videos on YouTube, bought all the supplies, and found a bunch of good but VERY reasonably priced pipes on eBay to practice on. Not rocket science and good results aren't hard if you are patient. In not time I found myself with 12 awesome pipes including a few early 1900s examples that came out beautiful. I stopped because I know what guns became for me and I don't need a damn pipe vault

 

[Wheelin98TJ]

IMO... For the highway it's pretty simple, do the chalk test and it'll tell you exactly where you need to be. For off roading, I think it's a preference and ultimately depends on the terrain. As others have said, there's a huge difference between independent suspension and a solid axle.

One thing to watch with the chalk test is if you're using wide tires on narrow wheels or if you're running a tire that has more of a crown to it. The chalk test might suggest pretty low PSI, like 23 for example. I don’t think I would run that low on a Gladiator.

 

[SargeDiesel]

One thing to watch with the chalk test is if you're using wide tires on narrow wheels or if you're running a tire that has more of a crown to it. The chalk test might suggest pretty low PSI, like 23 for example. I don’t think I would run that low on a Gladiator.

Over the years, I read of people running 26-28 ... if I remember correctly, they were usually a larger tire and heavy ply (E) ... but for the most part many trust the chalk. But I agree with your assessment... Great point.

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