Air Bag Pressure

[Crespro]

Hi,

For those of you with air bags on the rear axle and a fifth wheel, how much pressure do you use?

I started with 30 PSI and now increased to 38 PSI. About 2,750# of pin weight.

Crespro

[rhagfo]

JIMNLIN wrote:
With only 2750 lbs of pin weight I wouldn't think the truck would need air bags unless your carrying more "stuff" in the trucks bed over the rear axle or have a badly designed suspension lift kit.
I used bags on my trucks when I was on the roads but just to level the truck and make it less of a DOT target going through a scale house.
I seldom ran much over 25 psi in the rears on one ton DRW trucks/heavy GN trailers.

It is the soft spring issue with F250’s, carried that much pin and about a 600# in bed tool box, and didn’t need bags the difference between a Ram and a Ford

[Michelle_S]

My Dually rides much better when loaded than empty and I'm on OEM suspension with no add-ons now pulling 19.5K.

[Big1]

My pin weight is about 2900lbs I put about 30lbs and that seem to work find, don't need them but I had them from my other truck so instead of letting them sitting around I use them, well not my air bag but my controller by airlift.

[TXiceman]

Super_Dave wrote:

TXiceman wrote:
I am a retired mechanical engineer and I go with numbers and ratings. Equipment is designed and rated to be safe by engineers, not backyard mechanics. Believe what you wish and the best of luck on the air springs and over loaded trucks.

Ken

Ken, just curious, what's your response to severe truck squat well before your numbers and sticker ratings are reached?

First thing is to make sure of the weight and you are not overloaded.

I run air springs on my DRW to help the ride. My pin weight and fuel load put me close on the trucks capacity, but I am under. I run 35 to 40 psig which is enough to lift the truck enough to get it off the overload springs and get a less harsh ride. Without the air strings, it rides rough under load.

So if it is to improve load, fine, but don't count on them to handle overloads.

Ken

[capacitor]

I added air bags to a 2500HD when I got a lance camper. The specs say it was 2500 pounds so I would put 50 psi in them. I seem to remember the spec sheet said 1 psi for every 50 pounds. Now I have a small TT and I use 20 to keep it level. I quit using the load leveler bars as they are a pain. No problems so far and it has worked for 10 years.

[Crespro]

Hello,

Appreciate all the answers. I have about 300# to 400# RAWR reserve, so this is just a matter of the best ride. With the bags at 5 PSI, the ride is poor. 30 PSI is better and I now seem to like 38 PSI. The truck is fairly level at 38 PSI.

I think the best level is from 30 to 45 PSI for the air bags and the best ride. One of the YouTube popular shows for Rv's uses 45 PSI on an F-350 with a toy hauler.

Best,

Crespro

[Super_Dave]

TXiceman wrote:
I am a retired mechanical engineer and I go with numbers and ratings. Equipment is designed and rated to be safe by engineers, not backyard mechanics. Believe what you wish and the best of luck on the air springs and over loaded trucks.

Ken

Ken, just curious, what's your response to severe truck squat well before your numbers and sticker ratings are reached?

[Cummins12V98]

FlatBroke wrote:
I leave mine at the minimal when riding around empty, when I hook up it goes to 30, I just leave it there. Haven’t touched the buttons in years.

That is what I did with the 11 DRW. Empty 5psi and it would go to 30 when loaded. Wife would make basic adjustments from inside the cab.

First pic no air bags, second bagged at 30psi. Basically same ride height with 4,500# pin. Same roads with bags and Bilstein's made an amazing ride quality difference.

[TXiceman]

I am a retired mechanical engineer and I go with numbers and ratings. Equipment is designed and rated to be safe by engineers, not backyard mechanics. Believe what you wish and the best of luck on the air springs and over loaded trucks.

Ken

[garyp4951]

JRscooby wrote:

TXiceman wrote:

garyp4951 wrote:
I run 20psi just to help the coil springs on the dips at bridges.

TXiceman, my air bags say I can carry 5,000 lbs more. LOL

The air springs DO NOT increase the load capacity of the truck.
All you can say is the air springs an carry 5000#.
The truck is rated for what is stamped on the stickers inside the door jamb.

Ken

But all that means is if the manufacturer can prove you went over their rating they don't pay warranty claims. The only rating the law will enforce is the tires.

Ken, do you know what LOL means?
I was not serious, just kidding, laughing out loud.:)

[MFL]

MANY take the time to understand what the stickers mean. Some stickers involve a class, or registration number limit. Others can be a limit that involves the weakest link (as delivered from factory). If the weakest link is the available spring pack, this can be improved on, by using air bags, or other means. Of course the stickers do not self adjust, when you add more capability. You still need to keep the next weakest link in mind too. Tires/wheels may be next, so that may be the limiting rating.

Jerry

[FlatBroke]

I leave mine at the minimal when riding around empty, when I hook up it goes to 30, I just leave it there. Haven’t touched the buttons in years.

[JRscooby]

Some think that sticker on the door jam is a commandment from god, or at least a gov mandate. I once bought a few tractors that had a GVWR of 32,000 or less, (don't remember for sure, know it was 12 steer, 20 on single drive), and a GCVWR of 80,000. I did a lot of changing to make them do what I needed to do. Basically I used the engines and cabs. About a week after I put them to work driver got stopped for torn mudflap. LEO, matching VIN to paperwork saw that 80, looked at BOL, that showed GCVW of 110,000. Now normally my drivers would pay 30% of fine, but I needed them moving rock, so I told them it was all on me. By the time I went to court on the first one I had over 40 tickets in hand. Cost me a little with the lawyer, but the judge explained to that officer that the only number on that plate that was any of his business was the VIN
Now I was dealing with CMVs. But most LEOs are more likely to be strict with CMV, but not look at RVs
Now I'm not saying running over your ratings is a good idea, because it will cause handling issues, and wear parts faster.

[Lightning55]

It takes 60 psi unless I'm loaded heavy, then it takes 80 to level off the rig