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adamis's avatar
adamis
Nomad II
Jan 15, 2022

Let's talk air bags...

My 1999 7.3 dually has airbags installed by the previous owner. I've generally not bothered to inflate them unless towing a trailer with my Bigfoot camper (4000lbs loaded). Today while driving on California's 101 near San Jose I was bouncing along from our overtaxed and under fixed roads.

While bouncing up and down I had an epiphany that perhaps a little bit of air might help the situation. Typically I've run between 30 to 60 psi in the bags if I'm towing a trailer with the camper. If I have just the camper I have usually left them empty or at 30psi unless I'm on twisty roads where I might bump it up to 90psi. That being said, it seems app subjective to me. Hard to tell if adding air I'm helped at all or if it was just the roar improving in the section I was then on.

So those of you that also have airbags, what type of truck and camper weight do you have and what PSI in the bags do you run? What is your measurement of ride improvement other then subjective "feels better"?

36 Replies

  • I have Airlift bags that do not have an internal bump-stop. The instructions state that I must keep a minimum of 5 psi at all times, because the instructions made me remove the OEM ones.
    Check yours to see if this is a requirement with yours.
  • Some years back we had a post about air bag psi and a picture of a trucks broken frame rail right where the air bag was mounted at the top. Seems like the truck owner was using high psi in his bags to level his load.

    I used air bags on all of my one ton DRW trucks to level max (rawr) axle/tire loads when I pulled heavy GN trailers. DOT doesn't like a saggy looking truck.
    Air pressure needs varied between GM/Ford brands and even different year models in the same brands. The most psi I used was 35 psi in a older model Ford drw. The others usually in the 10-25 psi range.
  • X2 on HMS Beagle's well said statement.

    After 20yrs of running this setup (2002 F350 SRW, Lance 845) I don't bother to measure air bag pressure any more. I just inflate to level out so I'm not blinding oncoming traffic with headlights. Unloaded I deflate to around 5psi, best guesstimate. I've got the Firestone Ride-rites with added limit straps, extended helper spring bumps, and factory sway bar...really happy with this set up.
  • Like Buzz I find 10 pounds or so in my airbags when not towing or hauling something heavy provides the best ride in my 1500. That’s the minimum recommended BTW.
  • Unfortunately air bag helpers as typically installed are likely to stiffen the suspension, not soften it. In taking out sag they also support the weight, with a spring rate that is higher than the stock steel springs.

    Given the variability of roads, you would probably need in-cab adjustment of pressure and run over the same road a few time to really make a judgement.
  • I drive the same roads near San Jose. 2011 F350 4x4 dually CC lb with a 4600 pound (loaded) Lance 1055. I have upper and lower stable loads and Airbags (for when I tow the horse trailer). Not towing I may put 10psi in the airbags