Trail Blazer III
Airing down.
- Thread starter WrightRunner
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Pathfinder III
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I always error on the side of caution, I run my 35" KO2's at 16-18 that way I can still drive on a hard surface if my air up options fail. May not be driving fast but I can get to a place that I can get help.
Off-Road Ranger I
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Thought I would chime in with an example for snow running. Two jeeps, lockers front and rear, plus a ton of other equipment, went on a snow play day. We turned town the wrong trail, and before we knew it, we were pushing snow with the front bumper going downhill. Tried to back up the hill, nope. So, I used my winch to turn myself around (an hour later), and still could't climb back up the trail, nor could my son with his 37s and 5.7 Hemi in his jeep. So, we aired down to 8 pounds, and viola, up the hill we went. still wasn't easy, but instead of 3 winch pulls, we would have probably been in for double digits. We started at 16 pounds when we left, just not enough flotation...
I would weigh your vehicle and do your own testing, you may be heavier then the jeep.
With our 99 F250 we run E-rated 10 ply tires at 75 psi on the highway. We air down to 32 psi when we hit the dirt right away - this is to keep our teeth in place and nothing to do with traction. If I think it is needed we air down to 30 or 25 psi depending on the trail.
In sand I air down as needed - so far we have not needed less then 20psi.
Our truck is right at 8,000 lbs with out water and coolers added to it.
Advocate III
This is one of the best and most informative threads I’ve read in the OB forums, with a wealth of info from drivers with actual experience.
With a loaded long wheelbase GMC cargo van, no bead locks, hauling a trailer, I’ve found a lot of info online about airing down applies to much lighter weight, smaller, vehicles. This thread has been super helpful with practical info that applies to my situation.
Gracias, muchachos!
Sent from my iPad using OB Talk
With a loaded long wheelbase GMC cargo van, no bead locks, hauling a trailer, I’ve found a lot of info online about airing down applies to much lighter weight, smaller, vehicles. This thread has been super helpful with practical info that applies to my situation.
Gracias, muchachos!
Sent from my iPad using OB Talk
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Member II
Tire manufacturers have application guides based on weight of vehicle and other factors. For example, I'm running D rated BFG TA KO2s on a 5th gen Explorer. Standard tires suggest 32 or 36, but based on weight and the D rated tires, guide said to go 44 psi on pavement. Ride is comfortable and works great. At low to mid 30s does really well on mud and snow and ice, and can still drive on highway, but after a while you see the temperature band around edge of tires from not being properly inflated.
Proper inflation for application and rotating on a good schedule are basic tire maintenance items that really help tires last. So far I have about 40k miles on these KO2s and they still have 7-9/32 tread left.
I had E rated ST Maxx on a FZJ80. The application guide for that use said 45 psi. More if I loaded it down a of course. 70 psi on those was just too much for the LC unless I had a LOT of weight. Same tire on a suburban tow rig ran 75 psi though.
The chalk test is a good way to make sure things are right as wellx especially if you can't find the application guide :)
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I completely agree with you on the chalk test, after a while you get really used to what you're running, rig and tire wise, and it becomes second nature.
But if you switch vehicles you have to start over.
My little YJ was "spool welded" in the rear and never saw much pavement, so it stayed at 25 on and off the trailer, then down to 8 or 10 out on the trail, those were 35 inch BFG mud tires, on a beadlock.
The H3 is entirely different...
It weighs in at over 5,ooo pounds geared up for a weekend, with the 3 of us, plus the Murder Dog, so I spent a lot time looking at tires.
I basically ended up looking for the best dual purpose tread pattern, and strong sidewall that would work without beadlocks. It's still all new to me because I would run the YJ out on the trail, and it was just me and the Murder Dog on a weekend, nothing like going out for a week or more, so I went with two seperate sets of wheels and tires at first on the H3...
For camping and trail running I ran a 325/60/18, Maxxis Mud Terrain, not beadlocked wheels,with a 2 inch spacer (not an adapter), and kept an air compressor with us so I could run down to 12 or 15 pounds and back up for the street. Then when we got back home, I would switch back to the factory wheels with a 315/75/16 all terrain BFG tire and run those on the street, unloaded, at 35 to 38 psi.
I'm still learning about all this myself, and haven't been out on a real overlanding trip for more than a weekend, but the H3 will have a built in air supply, and only one set of wheels and tires.
This is a great thread, and the information here is helping me get this all sorted out, thanks y'all..!
Pathfinder II
Here's a little article we just updated for 2018 regarding the subject of airing down for both rigs and trailers:
Deflating for Overland Travel (2018)
Deflating for Overland Travel (2018)
Great article..!
Keep the plan simple and easy to remember.
Really good info, thanks Kevin.
Keep the plan simple and easy to remember.
Really good info, thanks Kevin.
I usually drive my rig at 1.8 bar on tar road. If I have ti drive dirt road for a long distance, 1.5 bar. Mud also at 1.5. Depending on the softness of the sand, I start at 1.2 bar and if necessary air out as needed. 0.3 bar is the lowest I am willing to go to as the tire might come of the rim at high speeds. The 0.3 is only for extreme circumstances.
Good article. Well worth a read!!!!Here's a little article we just updated for 2018 regarding the subject of airing down for both rigs and trailers:
Deflating for Overland Travel (2018)
Traveler III
Advocate III
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Nice article! thank you.
I have learned a little of this from my own research and experience, I've been airing down to 18-20 PSI on 265/75R16's using some generic Staun Knockoffs (The reviews on amazon were good, but I will be buying genuine Staun's as they leave a lot to be desired in my experience)
I have learned a little of this from my own research and experience, I've been airing down to 18-20 PSI on 265/75R16's using some generic Staun Knockoffs (The reviews on amazon were good, but I will be buying genuine Staun's as they leave a lot to be desired in my experience)
I'm pretty sure Staun is out of business now. I think 4 Wheel Parts sells another brand which bought the rights from Staun and are about the same price as the originals.
Trail Blazer III
I run 315/75/16 (34 1/2 in) and I aired down to 15 on my Full size Dodge ram with gear but aired up on paved road. I like to run no smaller then a 34 in tire because when you air down you'll drop in clearance to and I need clearance. It also depends on how rough the trail is, rougher = less air and smoother = more air so you'll have to call it as you see it. I'm old school so starter fluid and matches is how I set beads and air up all in 3 sec or seek other methods for setting the beads. Air down till you find what gives you a good ride for your type of vehicle. 15 psi works for me.
Great info in this thread and article.
For me, it depends on what I am planning on doing.
I have run everything from 15 PSI on just dirt road trails, to as low as 4 PSI in the snow.
I have 35" BFG KM2's running on Raceline Monster beadlocks.
Even before getting the beadlocks, I would go pretty low in the snow or sand.
As mentioned all over this thread, test your tires for what you are comfortable running at for a low pressure.
Every tire is different and the weight of the vehicle plays a role in this also.
My typical setting is 12 PSI for most trail running with mild rocks.
I have 3 sets of deflators, and they are all set differently.
One is at 15 PSI, the next set is 12 PSI, and the last set is 8 PSI.
Todd
For me, it depends on what I am planning on doing.
I have run everything from 15 PSI on just dirt road trails, to as low as 4 PSI in the snow.
I have 35" BFG KM2's running on Raceline Monster beadlocks.
Even before getting the beadlocks, I would go pretty low in the snow or sand.
As mentioned all over this thread, test your tires for what you are comfortable running at for a low pressure.
Every tire is different and the weight of the vehicle plays a role in this also.
My typical setting is 12 PSI for most trail running with mild rocks.
I have 3 sets of deflators, and they are all set differently.
One is at 15 PSI, the next set is 12 PSI, and the last set is 8 PSI.
Todd
Off-Road Ranger I
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weight, weight, weight, tire rating, & weight. I run 20 lbs on my trailer all the time with E rated BFG KM2s and that includes long distance interstate travel. The trailer weighs only 1,000 lbs fully loaded and sticks to the trail, big rocks, slickrock, and the highway like glue. My rig weighs in at 7,000 lbs fully loaded with E rated BFG KOs. General purpose trails I'll air down to 20lbs. For more serious trails I'll go as low as 18lbs but that is rarely necessary. I started elephant hill once at 14 lbs, that was overkill so half way to camp I pulled off and aired back up to 20 lbs. I run 34-36 lbs (front-rear) on the street in summer. In the winter I run 32-34 lbs. The OP has a 4Runner, loaded down he scale out at right around 6,200 lbs, which is a ton, literally a ton heavier than a JKU, let alone the lighter jeeps from previous generations. Even if the OP is running E rated rubber I'd never go any lower than 18 lbs. Andrew's video was a confirmation of what my methodology has been for decades. Good luck,, peace out.
