Off road tire pressure (for rocks)

[RuggedH2]

Anybody want to let me in on the off road pressure they feel comfortable with for rocks?

I have Toyo M/T 35's. As you can see, the tires have much "play" left in them. I have run from 20 psi all the way down to 15 for rocks.

I want to go lower pressure for the traction, but obviously don't want the beads popping. Does anybody here run lower pressure than 15 on the stock H3 wheels, with success? My friends with Jeeps routinely run 10-12 psi, but those rigs don't weigh what we weigh.

Thoughts?

[Sewie]

I've gone as low as 12 PSI, but usually run between 15-18.

[blindzebra]

day to day I run 45 psi. the ride is better, and the front wears much slower.

[Sewie]

BUT WHAT PSI DO U RUN ON THE DAY 2 DAY ?????THAT SEEMS 2 B THE MYSTERY.......

I run 40-42 PSI on the street. Anything over that and the Toyos start to crown.

[RuggedH2]

Thanks Sewie.

I'm thinking I'll run 12 this weekend. If that works ok, I might try 10. :D

I won't know if it works until I try.

That is unless someone already knows better and speaks up. ;)

[HummBebe]

Thanks Sewie.

I'm thinking I'll run 12 this weekend. If that works ok, I might try 10. :D

I won't know if it works until I try.

That is unless someone already knows better and speaks up. ;)

I personally wouldn't recommend anything lower than 15 for rocks. For snow or sand maybe. Keep in mind, when going over rocks, not only can you pop a bead, but you can seriously bruise a tire making it useless.

You can do anything you like, but I would advise against it.

[SR1355]

:iagree:

I'd run no lower than 15# on rock, I run 12# on sand but the isn't much to damage a tire on in the dunes...

Have fun this weekend you lucky dog....:beerchug:

[RuggedH2]

The problem with 15 is that there is enough pressure within the tire, that it still doesn't "conform" to the rock much at all.

I realize that even at 10, it isn't gonna "conform" around rocks like a bead locked wheel at 6 (or lower).

I'm looking for a balance here that I can live with. Bruised tires are a real possibility. So are broken parts. I think running less air may also add additional stress to the already weak front axle. The only plan I have to counter this, is limiting wheel spin and hop, (trying the old BTM) and driving it slow. (Good spotting will help, I'll have Neo watching them for me) :D

I'm gonna give the lower pressures a shot. See if it makes a difference. It might not be worth the gamble, we'll have to see. The H3 is a good rig, it isn't gonna be made into a great rock rig, by just lowering the tire pressure. Just looking for the right balance here, if it turns out to be safe, might make it worth it. I'm glad Toyo strengthened the sidewalls on these.

Thanks for the advice, I appreciate it.

[stagger_lee]

I usually just let all the air out, it gives you the most surface area. :giggling:

[RuggedH2]

Shut it fagger! :giggling:

that .02 worth 0 on this. ;)

[deserth3]

I ran fins and things with Jerry Seiner Hummer Happenings last month. Left the tires at 35 and didn't have any problems.
This weekend I'll try them at 30psi and see if there's any difference. I'm still running the stock 285's

[Desert Dan]

deserth3

You will notice a difference in traction and ride.

I like the tires to do half the work of the suspension

Lowering psi on harsh high-speed wash board roads makes a heck of difference too.

[usetosellhummer]

I like 18-22, they heat up on the trail. any lower you always risk a slip off the rim. i saw a guy do the lighter fluid trick to put the rubber back on his h1 rim. It was cool.

[RuggedH2]

I have a heavy ratchet strap and a can of brake cleaner if necessary. The compressor is on the truck.

If it does pop a bead it will suck, but shouldn't be anything to start bawlin about. Plenty of high lifts will be along on this trip.

[HummBebe]

Shut it fagger! :giggling:

that .02 worth 0 on this. ;)

:jump: :jump: :jump:

[RuggedH2]

Beebs,

I think stagger lee is OK. ;)

So far he didn't bring much to this discussion, but if I (n)ever wanted an opinion of how the liberal hippy commune community felt about the Bush Administrations handling of foreign policy; he'd be the first deadhead I asked. :D

Occasionally, threads around here have a way of going straight into the crapper. I was hoping to pull some experience and knowledge out it, before that happened. :beerchug:

[deserth3]

I was just pulling off my side rails and noticed my rear diff is wet. Hopefully I can run it to the dealer before work tomarrow.:mad:

When I had the tires at 35 the ride was still pretty good offroad. It'll be interesting to feel the difference at 30. I'm not crazy about going any lower, where I'm staying is about 20 miles from Neocon's house.

[stagger_lee]

Beebs,

I think stagger lee is OK. ;)

So far he didn't bring much to this discussion, but if I (n)ever wanted an opinion of how the liberal hippy commune community felt about the Bush Administrations handling of foreign policy; he'd be the first deadhead I asked. :D

Occasionally, threads around here have a way of going straight into the crapper. I was hoping to pull some experience and knowledge out it, before that happened. :beerchug:

Hey F you guys! haha j/k. What, like 4 people gave the right answer of 15-18 lbs depending on tires, so instead of of being a parrot and becoming the 5th douche to give the same answer I smart my a$$ off. Im just here for the entertainment and maybe try and get you to chuckle a bit while youre reading.


So here is a straight answer. Experience comes from equally heavy rigs, Scouts, FJ40s, and FJ80s, as I haven't really rockcrawled the H3, but sand and snow yes. I run 15 -18 lbs on rocks and snow. Loose rocks closer to 18lbs, flat slick rock (Moab Stylie) closer to 15lbs. Slow driving in sand a bit lower, but not usually lower then about 13lbs, and if I'm driving fast in the sand I want it no lower than 15lbs. We have run 10lbs in my brothers prerunner in Glamis, be he has beadlocks so it doesn't matter. Our rigs are pretty heavy so anything lower than 15lbs is pushing your luck I think. Hows that for a recap on the previously already perfect answers given. Thanks for givin me crap guys. Keeps me in line.:beerchug:

[RuggedH2]

Hey desert,

I hope everything is fine with your rig. We are planning to run some cool trails. I hope you can still make it. If you are just worried about loaning me your spare tire relax, I'll borrow Neo's. :D

[RuggedH2]

Stagger,

Have you ever popped a bead? You know that 15-18 is perfect, how? Lower pressure is better for rocks. There are hazards. That's why beadlocks have become so popular off road.

Unless you've gone low enough to pop a bead, I don't think you know the "perfect" answer for the H3. I see the common logic, but it's not so clear for every 4x4, many go as low as they can. Buggies commonly run 3 psi with beadlocks.

Thanks for "dumbing" it down for me. :giggling:

[stagger_lee]

Wasn't trying o dumb it down chief. :giggling:
I have popped a bead at 10lbs on my scout. I have popped a bead at 12lbs on rocks in my old FJ80. It depends a lot on the tires. The toyos seem to have a pretty stiff sidewall as well as the goodyear MTRs. BFGs aren't as stiff, and I had super Swampers before and they were like jello. I have not popped a bead on the H3 yet, because I haven't pushed my luck. There is really no perfect pressure. You can pop a bead a 15lbs if you hit an obstacle just right you know? I dont have the knowledge or experience in the H3 as some of the others on here, but I have been off roading my whole life, in multiple rigs and set ups, so I have really just come of with the perfect pressure that works for me and that I feel comfortable with. :beerchug:

I also would rather sacrifice a bit of extra traction by not running really low pressure in order to save me from down time on the trail. Im sure you could go lower then I do and be fine. Eventually I would like to get a set of beadies just for the trail to be used on the H3.

[deserth3]

Hey desert,

I hope everything is fine with your rig. We are planning to run some cool trails. I hope you can still make it. If you are just worried about loaning me your spare tire relax, I'll borrow Neo's. :D

Borrow my spare and it would look like you're driving on one of those donut tires.:D

[Hunner]

On my H3 with MTMTZ 33's with 3 ply side walls, which are 33.1 this shot is when I ran 20lbs. I was rolling over on the side wall alot and broke a piece off the edge of a couple of rims. I now run 26 in the rocks. I have one tire that got 4 slices in the side wall that run from the outside edge towards the middle. It is now on the rack for emergency use only.

[Hunner]

The second one is common where I wheel. Jagged shelves of shale and Ouachita stone, used to sharpen knives, stick out in narrow ravines and if you run too low with the sidwall pouched out, you get a cracked rim edge. 26lbs works for me.

[stagger_lee]

There you go perfect example of what works for you. You have loose rock, wet rock, solid smooth rock, jagged rock...you cant come up with a number that works for all situations. I like to run a little bit more pressure than what I think is a safe PSI, I dont want to be stressed out while Im wheelin. :beerchug:

Thanks for the pics Hunner. Looks like those (bridgestones?) have a little softer sidewall then the toyos, therefore higher PSI is ideal. Would you think that to be correct Hunner?

[Wisha Haddan H3]

Speaking of popping a bead at low pressures, has anyone ever tried (or seen) Staun beadlocks (http://www.staunproducts.com/beadlock.php)?

[RuggedH2]

On my H3 with MTMTZ 33's with 3 ply side walls, which are 33.1 this shot is when I ran 20lbs. I was rolling over on the side wall alot and broke a piece off the edge of a couple of rims. I now run 26 in the rocks. I have one tire that got 4 slices in the side wall that run from the outside edge towards the middle. It is now on the rack for emergency use only.

Damn that sidewall is much more flexible than the Toyo. I have read that the Goodyear wranglers are also very flexible. The pic I posted in the beginning of this thread was of the Toyos at 15. They aren't flexing over the rocks hardly at all.

I'm also glad that the rock here is not like the shale and knife sharpening stone you have there. You can still rip a tire here, but that looks heinous.

[RuggedH2]

Speaking of popping a bead at low pressures, has anyone ever tried (or seen) Staun beadlocks (http://www.staunproducts.com/beadlock.php)?

I have seen those, they look very interesting. The list didn't show a 16x7.5 though.

[Hunner]

I forgot to point out those "are" the Bridgestones in the pictures before I dumped them for the MTMtz. Its an age thang, senior moment. The Mt are stiffer side walls but Im still running 26 in the conditions I wheel. Had one H3 run 15 on Bridgestones and she got a rock stuck between the wheel and tire! Baseball size!
Here is another shot, with the Bridgestones and other stones in a "mine field" This is one of the reasons I decided on the MTmtz. It seems to be a tougher tire so far and grips on those side lugs which protect the sidewall. Guess I got over the new and have not shot many new "tire shots" oh boy now I have a mission..............oh and the Mtz got into those flares so I had to take them off. The side lugs rubbed in these conditions. They also rub my front sway bar in certain conditons. Thus Im glad I did not go for 35 in this tire.

[Hunner]

Sorry but I found a shot of the Mtmtz with 26 so I thought some might like to see that. I like that amount of bulge to protect the rim but not much more.

[stagger_lee]

Hunner The Mtz's, are they 305's? or 285's. I have read good reviews about sidewall strength on those tires. 03H3 you mentioned the Goodyears having a soft sidewall, were you refering to the MTRs or the RTS garbage that come on the H3s stock? Just curious because the MTRS have one of the highest strength rating for sidewalls 2nd only to the Toyos. The Toyos have just recently within the last year been recognized for the quality tire that they are and were rated above the Goodyears. Probably helps that Robbie Gordan runs them and help develop them and ran some crazy distance in Dhakar the year before without having a flat. :beerchug:

[Desert Dan]

The weight of the vehicle has a lot to do what pressure you can run.

A dune buggy or a 3500lb Jeep can run lower air pressure than a fully loaded H3 (assuming similar tire sizes).

PS You don't want to pop a bead on a side hill!

[stagger_lee]

The weight of the vehicle has a lot to do what pressure you can run.

A dune buggy or a 3500lb Jeep can run lower air pressure than a fully loaded H3 (assuming similar tire sizes).

PS You don't want to pop a bead on a side hill!


Weight is a huge factor. My sandrail weighs all of 1400 lbs. 5-10lbs isn't questionable to run.

Nomo - the last 4wheel drive mag or off road or whatever, that had the tire test, the Toyos were #1 all around! good stuff. :beerchug:

[RuggedH2]

OK, obviously the tire you are running is gonna make a big difference with what pressure you feel comfortable with.

The terrain and other variables should also enter into your decision.

With that in mind, the 35" Toyos on my truck have a thick sidewall and are just broken in, 10,000 miles.

I still believe that for the most part, the lower the pressure the better the traction. I have been looking for the balance of all around ability while remaining as safe as possible.

My conclusion only applies to my rig, the Toyo's, and in Moab. (frankly because I'm hooked, it seems to have it all, and as close as it is to me, why drive anywhere else?):D

Now, I ran Poison Spider Mesa with 13 psi. Good traction, and some good flex in the sidewall. I ran Metal Masher with 12, about the same. Hell's Revenge and Seven Mile Rim with 11. I also drove highway and freeway with 11 psi. For me, 11 psi is safe and provides the level of flex in the sidewall without worrying about the bead. I had all the weight of the vehicle on two tires at severe angles, and I didn't worry about the beads at all. 11 psi provided great traction and conformed around the rocks well.

I personally wouldn't hesitate to run even a little lower in sand or for enhanced traction if required.

Sorry for the long post, maybe someone else can use the information in this thread someday.

[RuggedH2]

:beerchug: 11psi ;)

[RuggedH2]

Hunner The Mtz's, are they 305's? or 285's. I have read good reviews about sidewall strength on those tires. 03H3 you mentioned the Goodyears having a soft sidewall, were you refering to the MTRs or the RTS garbage that come on the H3s stock? Just curious because the MTRS have one of the highest strength rating for sidewalls 2nd only to the Toyos. The Toyos have just recently within the last year been recognized for the quality tire that they are and were rated above the Goodyears. Probably helps that Robbie Gordan runs them and help develop them and ran some crazy distance in Dhakar the year before without having a flat. :beerchug:

Stagger, I don't think I said "soft", I think I said flexible, not necessarily the same thing. For instance, fiberglass can be flexible, but doesn't have to be soft.

http://www.google.com/search?hl=en&q=goodyear+wrangler+flex