Tire Pressures

[Metal Twister]

I haven't had any experience with airing down for crawling in rocks. I have been going to the desert and airing down sand cars, and  bikes my whole life. Is there a rule of thumb as far as what the minimum pressure should not exceed on a non bead lock rim? Does the rim width make a difference? And is it worth it to run nitrogen, co2, or just stick to compressed air?     

[jeffm1964]

Generally I run between 9-10 psi and I have dropped down to 5 psi a few times. I'm not running bead locks yet just a matter of time.

[Metal Twister]

So what does 5 lbs do for ya that 9 lbs wont?

[jeffm1964]

the ability to wrap around rocks ect maybe a little better it is a little funny feeling the way the sidewall rolls around

[Big boy]

I've gone down as low 9psi but I've been to chicken to go any lower with out bead locks. If you run regular air you could just throw on an on board compressor, if you run nitrogen you have to have one those cool tanks (I forgot what there called) and have to have someone fill it up for you. I guess what I'm getting at is that the compressor would be a one time cost and the nitrogen would be more $$$. I have some friends that have run nitrogen and they claim there is really no difference.
                                                        Just my 2cents.........Bigboy.

[HURLEYGO3]

I will drop down to 3psi if i don't need the extra ground clearance. But most of the time i like to run about 5psi. As for a non beadlock wheel it depends on the wheel and tire. Some rims will hold a bead better than other. I had to run a set of Krawlers with out beadlocks for a trip and they would loose a bead at 12psi. You will just need to play around and see what works for you. No need for nitrogen, just get a power tank and they are like 10 bucks to fill up.

[hammeredtoys]

I run about 8 psi when rockcrawling seem to work good no problems with the beads, tires are tsl 35x15.50x15

[StvDiego]

I run about 9-11psi using auto deflaters. Works very well and haven't lost a bead, yet. Right now I'm using the ol reliable Tsunami Air Compressor.

I'll eventually go to Co2, filling a 10lb tanks costs $10 - $15 depending on where. The Power Tanks setups are nice but if you want to save some $$$ head to The Beverage Factory during their semi-annual sales, brand new aluminum 10lb C02 tanks with a regulator are <$70, regular price is $89.

[lqcj8]

I run @ 6psi , I lose a bead sometimes, but thats what OBA is for. My 8 has a engine driven comp. The rubi has a powertank

[4x4grey88]

I run 10-12 psi on 33" Procomps. I work the trails fairly well and have not lost a bead yet (knock on wood)

[84socal]

tire size doesnt really play a factor    its the tire width    and rim width combo     

i used to have a set of 35x12.5x15 bfg mt on 15x10 rims   couldnt air down below 12psi without blowing the bead
 then i got another set of the same tires on 15x8 rims dropped to 6 psi all day never lost a bead


now im running 315 75r 16 in toyo muds on 16 x 8 rims had them down to 7 psi  the last run at the hammers  never even had a doubt about blowin a bead 

but un less ur doing serious hard core rock crawling  i reall dont thing thers a need to drop below 10 psi

[DavidWymore]

As you can see from the posts, it's very subjective.

 I used to run 35x1250 MTRs on 15x8" wheels. Only burped air once, and it was special circumstances.


My 44" tires on my blazer will burp air if I get below 15 or 20 psi, but that's because the tires have a heavy duty truck style bead which is too big for the bead land area on my wheels. I may glue them on with windshield installation glue or beadscrew them.  

I used to run 38" x 13" tires on 16"x7" wheels on the blazer...they'd stay on with NO air...and the tires were heavy duty military, so they'd hold the rim up off the ground a bit with no air too.

General rule of thumb is to go as low as you can without losing beads and/or clearance. Also, the lower psi you go, the more vulnerable your sidewalls are. Smaller tires-more pressure-bigger, tougher tires, less pressure....vehicle weight plays in too. Generally, wider tires on narrower wheels will stay seated better. Different tires and wheels have slight variances in diameter and safety bead size too though.