How high should I go?

[FranknKaren]

I have air bags under the TC. My question is how much air do I put in them. Right now the height with the airbags inflated is the same for front and rear fenders and the truck is level. The TC is not quite level, 1 number off on the bubble. The spring bumpers are not touching overload springs. Does this sound ok or do I need to adjust?

[FranknKaren]

I have air bags under the TC. My question is how much air do I put in them. Right now the height with the airbags inflated is the same for front and rear fenders and the truck is level. The TC is not quite level, 1 number off on the bubble. The spring bumpers are not touching overload springs. Does this sound ok or do I need to adjust?

[Hemi]

Hi, I have the f350, 1999 crew-diesel like yours; it carries a bigfoot 3000, ~4200 lbs.

I run my rear air bags at about 80-85 lbs. On several trips FL to Pacific Northwest and return I have never had to add air. The system is very reliable. The inflated bags raise the rear of our unit several inches; the truck/camper is level. Without the airbags, there was a terrible sag and handling was difficult.

Note: I also have rancho 9000 shocks all the way around. The rancho/air bag is a win-win combination in my opinion.

Iver (Hemi)

[RedneckExpress]

You may want to look into getting bump stop extensions for your overloads so they engage still, lifting the load off them will increase your side to side sway, adding the bump stop extensions will help reduce the side to side play a bit that comes with the load riding on air.

[Harald]

Hi Frank n Karen,

I think you are right on. I put enough air in my airbags to level the truck because it handles better when level. It's usually about 70-80 psi to get level with my 4000-4500lb camper. At that attitude, the overloads are not touching. If I was relying on the overloads only with no airbags installed, the truck would be way too low in the rear.

The airbags do a pretty good job of stabilizing the truck. The key is to make sure the airbags are plumbed so that each side is seperate (do not "T" both air lines together). When the truck sways to one side, the pressure in that bag climbs and therefore resists further compression. Like Iver, I also have the adjustable Rancho shocks and they make a dramatic improvement in the amount of sway. I crank the rears up to max dampening when the camper is loaded.

I've never had any leaks in many years of using my Firestone bags, but I have thought about adding extensions to my overload contact perch. If I load my camper with minimal pressure in the airbags, the airbags could get damaged because they would compress too much. If I have some time one day, I plan on getting some hockey pucks and drilling them (with appropriate countersinks) so that they replace the overload contact point and cause the overload spring to contact earlier. This might even eliminate the need for airbags, although I would still keep mine because I like having the adjustability (on uneven ground I sometimes use the airbags to level the truck/camper when camping).

[Mexray]

Now that I've just installed air bags on our F-350, I am using 75 psi one side and 55 psi other side to level the truck for/aft and side/side...I guess one of my springs is a bit more 'tired' than the other!

The single top overload leaves are now not touching the frame brackets, as others have noted. I believe this is a good thing! The ride is much, much better riding on the airbags! When the load causes the overloads to flex against their frame brackets, you 'ride' goes out the window - those overloads are just that - overloads, and when 'loaded' you have effectively lost the better 'ride' qualities of the normal, much longer spring pack.

While it may tend to help stabilize the sway factor to some degree, bringing the overload leaf back into contact with the frame brackets by using spacers, etc., will again impact the 'ride' when the shorter overload lead flexes instead of allowing the airbags to do their 'thing'.

A heavy sway bar, good HD shocks, and airbags are the best solutions, in my opinion, for an improved ride and sway control.