What do air bags do?

[rbpru]

After 60,000 miles, of which 23,000 miles are towing, I am getting some bounce in the rear. The shocks are the OEM.

Somebody suggested I add air bags to stiffen rear. My WD hitch keeps the rig level and the F-150/Dutchmen combination tows fine.

What do air bag do and would they improve anything while towing.

[Carrier]

93Cobra2771 wrote:
I've never had mine bottom out unloaded. They recommend 5psi to keep them from wearing with no psi. I suppose it's possible your rear leafs may be losing some spring or something. Never come close to bottoming out with 5 psi.

This truck of mine does ride really well without the airbags so it could have softer springs in it. If I adjust the bags when driving to the road I'm on it floats just like a 1975 Caddy Eldorado I used to have.
However I have to have at least 10 to 15 psi in the bags so it doesn't . I have 70,000 miles on it and has been the same since new.

[93Cobra2771]

bobndot wrote:
Measure the front wheel well height of your normally loaded truck before hitching up and then again hitched up with a WD system. Keep that front wheel well height as close as possible. Allow your trucks rear axle and the trailer axles carry the load.

Actually, current instructions for most trucks say to have the front fender height 1/2 the distance, as opposed to being back to stock.

In the event of a panic stop, this keeps the rear wheels loaded better and makes the rig less likely to jackknife...

[bobndot]

rbpru wrote:
Since I use the WD hitch to bring the TV level, I was thinking air bags would reduce the amount to bounce, perhaps making it easier on the new shocks.

not necessary to add one more calculation to your proper hitching set up formula.

this post has info for you
http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/24058135.cfm


I agree with the people that suggested, change the shocks to BILS or 9000's . I did that, it offered a nice difference over OEM,both towing as well as solo.
I used both brands on the same truck and between the two, found no difference in ride except the dials rusted shut on the adjustable RS9000's , from road salt.
The BILS are fine for towing applications.

I have AB's as well as quick disconnect stable loads on my TV and I don't need them anymore, now that I tow. My old AB's and SL's just go along for the ride and enjoy their vacation now, they are retired until I get another TC. 🙂

AB's are popular on TC's to level the load while hauling opposed to towing where the spring bars do that for you.
Leave off the AB's to allow the spring bars to properly do the job they are designed to do. You will not be stressing the new shocks if you set things up correctly.


Measure the front wheel well height of your normally loaded truck before hitching up and then again hitched up with a WD system. Keep that front wheel well height as close as possible. Allow your trucks rear axle and the trailer axles carry the load.

[myredracer]

I installed Bilsteins in our old F150 and our current F250. They make an amazing difference. For even better bounce control, go a step further and install shocks in the TT.

[rbpru]

Since I use the WD hitch to bring the TV level, I was thinking air bags would reduce the amount to bounce, perhaps making it easier on the new shocks.

[93Cobra2771]

I've never had mine bottom out unloaded. They recommend 5psi to keep them from wearing with no psi. I suppose it's possible your rear leafs may be losing some spring or something. Never come close to bottoming out with 5 psi.

[Carrier]

93Cobra2771 wrote:
5psi unloaded. When loaded it's a different story. 5 psi is what the manual recommends when not towing. Some do add more, as they like the stiffer ride. And some use them for a cheap way to lift the rear (not recommended by Firestone).

I have a Hellwig rear sway bar as well - made a very nice difference while towing, and even unloaded it made a big difference.

I'm talking about unloaded.

[93Cobra2771]

5psi unloaded. When loaded it's a different story. 5 psi is what the manual recommends when not towing. Some do add more, as they like the stiffer ride. And some use them for a cheap way to lift the rear (not recommended by Firestone).

I have a Hellwig rear sway bar as well - made a very nice difference while towing, and even unloaded it made a big difference.

[Carrier]

93Cobra2771 wrote:
One advantage for airbags is getting the rear back to unloaded height, which puts your headlights back into great alignment for nighttime driving.

Another advantage is that they give a better ride than leafs, in my opinion. Often, the rear springs ride pretty soft, especially in 1/2 tons. To me, the bags give a better ride than the leafs, with infinite adjustability to boot.

Keep in mind, if you raise the rear ride height, you will need to adjust your WDH to compensate.

It is nice to air them up for towing, then drop them down to 5psi and enjoy your stock ride while not towing.

I have a 2010 F150 just like the one you have except it has a 5.4. I also have Firestone bags but no way I can only have 5 psi in the bags as they will bottom out. I need at least 12 psi in them.

[LVJJJ]

I use Monroe Load Adjusting shocks on the back to stabilize the rear end to keep from bouncing and rolling. They don't increase capacity, just keep things stable. I think its too easy to assume that air bags will increase the carrying capacity of the TV, but it's dangerous to make that assumption.

Our '04 Envoy is equipped with Billstein's from the factory and they sucked. Replaced them with Monroe.

[dodge_guy]

i would also recommend new shocks all around. Airbags are good for heavy weights and/or carrying stuff in bed while towing. Manuf have to make a compromise on ride quality and carrying ability. That is where the aftermarket steps in and offers options to meet each persons needs.

I'm running airbags on my X and they make towing much more enjoyable knowing the factory springs on Excursions were designed more for ride and less for carrying ability. The airbags help out when needed!

[Community Alumni]

With the 5th wheel guys and gals, airbags help level the truck. Not really needed in the TT world since the WDH hitch should be doing that job already. They also can help fine tune a ride based on the amount of weight it's currently carrying. Typically this is really effective with heavy weights. With the light loads we carry, relatively speaking, ride quality can mostly be controlled with shocks, tires, and WDH adjustments.

A lot of shock manufacturers recommend replacing after 50k mile of typical use. You've carried a good load for just about 40% of those miles from what I can tell so it's probably time for replacement. At your weights and 60k miles of pleasantness, I wouldn't waste the time with putting air bags in. New shocks will definitely help improve your experience. I have Bilsteins and they're worth every single penny.

[beemerphile1]

rbpru wrote:
After 60,000 miles, of which 23,000 miles are towing, I am getting some bounce in the rear. The shocks are the OEM.

Somebody suggested I add air bags to stiffen rear. My WD hitch keeps the rig level and the F-150/Dutchmen combination tows fine.

What do air bag do and would they improve anything while towing.

What air bags often do is fool people into thinking that their overloaded vehicle is not overloaded.

Sounds like you are ready for new shock absorbers.

[noteven]

My 12000lbs full air rear suspension with 4 air springs uses full hydraulic shock absorbers not gas shocks. They are Skyjacker somethin somethin's.

When you add air bags to steel spring suspensions you are adding spring capacity and rate. You need to match shock absorbers to control the pogo stick action.