Anybody have any general rules of thumb when lowering tire pressure for off-roading?

I know the military does, but havent the time to research

Also, anybody use those 12volt, 250lb cigarette lighter powered air pumps?

Any good? worth it?

thanks in advance, mv

I do use the portable pump to keep my tires up to pressure,they work fine as far as I'm concerned! Even used it once to pump up a completely flat tire that had a slow leak to get it repaired.

For stock size tires, I'd recommend airing down to 22-24 psi offroad. This gives you a safe margin as to not pop a bead. For larger tires, many go as low as 16-18 psi without problems. Get beadlocks and you can go to 0 psi :)

With lowered air pressure, highway speeds should be limited to avoid stressing the tires and/or causing uneven tread wear. Also, onroad handling will be more sluggish and cornering will feel more uneasy.

I think you should be able to safely air down to the upper teens, unless you are running some exceptionally small tires. What size are they?

If you are looking to buy a compressor, I recommend the TruckAir. It is rated tops of the pumps under $150 or so. You should be able to get one for $35-40.

I have the TruckAir also. Worked flawlessly last weekend to air up back to street pressure on my 33's. I aired them down to 20 lbs and had good results while offroading.

Jim

Thanks fellas,

I'm running standard all-terrains on my stock X (gotta winch though) and probably will go for a Wally World special in the $30-40 range.

I dont see me doing this all the time, but it has been raining hard for the past week here in Ga., I expect some muddy trails for my following weekend trip to the 'church of the pines'

thanks again, mv

Anyone have links to the aforementioned TruckAir compressor unit?
Right now I use the $10 unit from Wal-mart. It works but takes forever.
I just can't hang with $200+ for the QuickAir but if something decent is available for a reasonable price, I'd like to take a look.

I usually run in the 10-15psi range when I am off-road. I have an ARB compresor that does the job of airing up but isn't the greatest. I will convert to OBA using the A/C system someday.

Take a look at Checker or WalMart. Both have the TruckAir. I used their compressor before I got the QuickAir and it works. It's not as good, but the price is there. For airing up tires......I'd say go for it.

i didnt see it at walmart today... where should I look? i looked by the air compressers... what is checkers?

http://www.campingworld.com/browse/skus/index.cfm?deptID=5&subOf=235,34&skunum=13832

Try by the auto section at wal-mart. Checker is an auto parts store(Kragen) is the same back there I think??

http://www.canadiantire.ca/media/images/Automotive/TireMaintenance/AirPumpsCompressors/0095043_450_CC_d0c3.jpg


The TruckAir is made by a company called Interdynamics.
It's listed here for CDN$79.99 at Canadian Tire.

just thought about it.......decieded to sell my TruckAir. Check out the For Sale forum for more info

I air down to 24-25 psi with my stock 235 75 R15 tires. I use a "Power Tank" except I made it myself for a fraction of the cost. For those of you unfamiliar with a Power Tank, it is CO2 air and it works great to run air tools and airs up tires in no time. For me it takes 20 seconds per tire from 25-35 psi.

leebo i called the truck air first did you get that email?

I saw your post in the other thread. Email with your info and I'll find out the shipping costs.

I just upgraded to ARB's with a Quick Air compressor.

I have a Truck Air, in the box - never used except once to test.

For Sale, $30 + shipping

like bill/rangerx said teens are good. when i went to los coyotes with rangerx, tdavis and rockranger i ran 13 all the way around. i have bfg at kos 313x10.5x15

We have a portable pump from ACDelco, called AutoMatic Air. Its rated at 260 psi and has a little dial that you adjust, like on a stove. It also has an attachment where you can air up things like basketballs, footballs, etc. The cord you air the stuff up with is about 2.5 feet long, and the cord you plug in the lighter is around 6 feet long. We havent ever used it yet except for airing up sports equipment, but for tires I doubt it is very fast, but it'll get the job done. And it measures 9 1/4 inches long, 7 1/4 inches wide, and 3.5 in. tall, so it stores easily. Good for emergencies, but I wouldnt use it if you wheel and air up alot.

We have the Truck Air unit.. We've had it for year.. I have since cut the end off and put on a real air chuck. I had a quick connect on there so I could use a longer hose (20 ft) but it was a pain to store in the truck.

I'ved aired up 10 tires in a row in 100+ degree weather and never had a problem. Most small compressors will fry if you try to do a few 32" tires.. but the Truck Air compressor has a fan on the motor to keep it cool. the only part that has ever died on it was the on/off switch.. a $3 part that took me 5 minutes to replace.

BTW.. I just saw them at Super K (kmart) last week in the car section.. for about $50ish

~Mark