Airbags--what exactly do they do?

[CMunrock]

My 5th wheel pushes on my rear suspension a little, so it's sagging a bit. I still have good control and power, but wondering if airbags would be of benefit. I've had friends install them on their trucks, but I've never known exactly what they do. Obviously, they cushion and smooth out the ride, but do they also serve to stabilize and offset smaller payloads (e.g. difference between 3/4 and 1 ton)?

Thanks--appreciate any feedback. Any estimates of prices would be good also.

[Drew_K]

Old-Biscuit wrote:
Airbags help with a sagging rear end (on the vehicle!)

Provide some extra shock absorbing effect

THEY will NOT increase load capacity.

I could not have said it better. The sagging is more than just a visual thing. If the rear sags enough you will start hitting the bump stops, resulting in a very harsh ride. The air bags are installed in place of the bump stops and bring the rear back to level so that the suspension can work where it's supposed to.

[Cummins12V98]

bound4fl wrote:

Cummins12V98 wrote:
I don't think people understand when a truck is loaded with a "full load" it will set level. There is nothing wrong with that at all. If the rear is sitting lower than the front it is usually overloaded and air bags will not keep it from being overloaded.

My Dually sits "level" with 4,500# pin weight it is not overloaded I added airbags to help even out the rough roads and only air them to 30#. That pressure does not change ride height and makes the fide smoother.

Most of the time airbags are a BandAid. Get the proper TV for your RV.

Unless you did like me. I added 2 inch front level blocks to my front end so it would ride level when I'm not towing. Then I added air bags to rear to get off overload springs.

Remove the blocks and drop the bags and your truck will ride better but I know that is not the LOOK you are after.

[bound4fl]

Cummins12V98 wrote:
I don't think people understand when a truck is loaded with a "full load" it will set level. There is nothing wrong with that at all. If the rear is sitting lower than the front it is usually overloaded and air bags will not keep it from being overloaded.

My Dually sits "level" with 4,500# pin weight it is not overloaded I added airbags to help even out the rough roads and only air them to 30#. That pressure does not change ride height and makes the fide smoother.

Most of the time airbags are a BandAid. Get the proper TV for your RV.

Unless you did like me. I added 2 inch front level blocks to my front end so it would ride level when I'm not towing. Then I added air bags to rear to get off overload springs.

[ol__grouch]

It depends on which air suspensipn you want to add. There are air bags that add cushion. There are also air springs that REPLACE the leaf or coil springs. A lot of large trucks use these. Depending on how it is set up, you can add spring capacity but you will still be limited by your axle. Running a LOT of weight on a full load bearing axle, like a 1/2 ton, and you can easily snap an axle.

[Cummins12V98]

I don't think people understand when a truck is loaded with a "full load" it will set level. There is nothing wrong with that at all. If the rear is sitting lower than the front it is usually overloaded and air bags will not keep it from being overloaded.

My Dually sits "level" with 4,500# pin weight it is not overloaded I added airbags to help even out the rough roads and only air them to 30#. That pressure does not change ride height and makes the fide smoother.

Most of the time airbags are a BandAid. Get the proper TV for your RV.

[mdamerell]

For us when I hooked my 5er I'm was 1/4" off the overloads. When I would hit a bump I'd get 2 bumps. One from the road and one when I bounced off the overload springs. By adding a set of Firestone air bags I lifted my rear back to normal ride height and gave myself about 2" of clearance from my overload springs which gave us a better ride.

[hmknightnc]

spoon059 wrote:

sdetweil wrote:
except that technical tag on the door post that says 10,000 gvwr for f250, which is what the states recognize.
will it work, probably, lots of people do it.
I traded my 250 for a 350 dually so I wouldn't have to find out.

In a lot of states you can register the vehicle for whatever weight class you want. The state only cares that you are paying the right fee to register. My Tundra is rated for something like 7200 lbs GVWR. If I wanted to pay more money every 2 years I could register it for 8800 lbs GVWR. If I was ever pulled over and weighed, I would ALWAYS be under 8800 lbs.

The weight ratings are for warranty work. The manufacturer feels comfortable that manufacturer warranty claims will be manageable below a certain weight. Its not about braking power or safety as far as the manufacturer is concerned... its about reducing their own liability.

If you are involved in a wreck and get sued by some ambulance chaser, they are going to start looking really close to your weights. Even if you are within your manufacturer weights, they can still try to sue you. Lets be honest, an empty pickup truck handles different that a pickup truck that is loaded to its max payload. Empty its going to stop faster than loaded. Some dirty lawyer can still bring a suit even if you are within your "legal limits". Of course its a LOT easier to make that claim if they find you over those arbitrary limits...

That's completely true. While you can ignore GVWR as long as your registered for the actual weigh you still have to be within Axle and Tire ratings. Those are DOT legal requirements.

[spoon059]

sdetweil wrote:
except that technical tag on the door post that says 10,000 gvwr for f250, which is what the states recognize.
will it work, probably, lots of people do it.
I traded my 250 for a 350 dually so I wouldn't have to find out.

In a lot of states you can register the vehicle for whatever weight class you want. The state only cares that you are paying the right fee to register. My Tundra is rated for something like 7200 lbs GVWR. If I wanted to pay more money every 2 years I could register it for 8800 lbs GVWR. If I was ever pulled over and weighed, I would ALWAYS be under 8800 lbs.

The weight ratings are for warranty work. The manufacturer feels comfortable that manufacturer warranty claims will be manageable below a certain weight. Its not about braking power or safety as far as the manufacturer is concerned... its about reducing their own liability.

If you are involved in a wreck and get sued by some ambulance chaser, they are going to start looking really close to your weights. Even if you are within your manufacturer weights, they can still try to sue you. Lets be honest, an empty pickup truck handles different that a pickup truck that is loaded to its max payload. Empty its going to stop faster than loaded. Some dirty lawyer can still bring a suit even if you are within your "legal limits". Of course its a LOT easier to make that claim if they find you over those arbitrary limits...

[sdetweil]

spoon059 wrote:
... In theory, since everything else is the exact same as a 1 ton truck and the airbags take that additional weight, adding bags to a 3/4 ton truck would take away the only difference from a 1 ton.

Just saying, not advocating.

except that technical tag on the door post that says 10,000 gvwr for f250, which is what the states recognize.
will it work, probably, lots of people do it.
I traded my 250 for a 350 dually so I wouldn't have to find out.

[Chopperbob]

Look into super springs.

[Ron3rd]

Agree with all of the above, and another option is Timbrens which are worth a look too.

[spoon059]

Old-Biscuit wrote:
THEY will NOT increase load capacity.

Legally, you are 100% right. However, consider that on some 3/4 ton trucks the ONLY difference between the 3/4 and 1 ton is the suspension. My friend has a F250 (early 2000's with the 6.0). His frame, axle, gearing, brakes, shock absorbers, wheels are the EXACT same as the F350. The ONLY difference is the suspension... I believe just overload springs.

I believe the Firestone air bags are rated for 5,000 lbs. In theory, since everything else is the exact same as a 1 ton truck and the airbags take that additional weight, adding bags to a 3/4 ton truck would take away the only difference from a 1 ton.

Just saying, not advocating.

[Old-Biscuit]

Airbags help with a sagging rear end (on the vehicle!)

Provide some extra shock absorbing effect

THEY will NOT increase load capacity.

[sdetweil]

you don't get extra capacity, but you get more 'spring' in the rear. (they are also called Air Springs)

so you can level the load with a little air in the bags. they support 5-100psi each.

I even have them on my 2012 F350 Dually. (which seems to want to use the overload spring way too soon)..