Montana Owners Club - Keystone Montana 5th Wheel Forum - View Single Post - Super Spring, helper springs, air bags???What's yo

rickfox · 12-20-2005, 01:24 PM

Good Evening All,

I recently installed a set of the Firestone air bags - helper springs. The installation went well with little trouble. Be careful when purchasing them as they come in a kit that is taylored specifically for the vehicle they will be mounted on. I finally called their customer service to get the correct kit part number - I had previously gotten 3 different part numbers from 3 different distributors.

My only disappointment is that they are sensitive to the air pressure used, and the kit does not come with the ability to simultaneously air up both springs to the same pressure. I suggest you make this modification.

The problem is this: each 1 PSI supports approximately 50# of weight, thus 10 PSI will counter act 500# of added pin weight, which typically will be more than enough to level out you TV. But since the air volume of the springs is small, accidently letting out just a small amount of air while checking the pressure can make several pounds difference in the actual pressure. Additionally, you have to get both springs fairly close to the same PSI. Accomplishing this can easily take 5 minutes of fooling around. And, of course, the PSI changes with temperature by as much as several PSI. Keeping things just right is somewhat of a pain in the ----. But they do provide the needed leveling, and with a good digital pressure guage, a hand pump, and a little practice, things work just fine.

And last, but not least, most of the time the TV is already over its GVWR and adding more suspension to level it out does nothing to help this problem, and most 3/4 ton TV's have a max rear axle rating of around 6,000# with upwards of 3,000# already being used up with the weight of the empty TV. For example, my 2500HD can handle only 2200# before exceeding GVWR, and approximately 2900# pin weight before I exceed the 6,000# rear axle rating.

12-20-2005, 01:24 PM	#4
rickfox Montana Master Join Date: Jan 2005 Location: Royse City Posts: 520 M.O.C. #2959	Good Evening All, I recently installed a set of the Firestone air bags - helper springs. The installation went well with little trouble. Be careful when purchasing them as they come in a kit that is taylored specifically for the vehicle they will be mounted on. I finally called their customer service to get the correct kit part number - I had previously gotten 3 different part numbers from 3 different distributors. My only disappointment is that they are sensitive to the air pressure used, and the kit does not come with the ability to simultaneously air up both springs to the same pressure. I suggest you make this modification. The problem is this: each 1 PSI supports approximately 50# of weight, thus 10 PSI will counter act 500# of added pin weight, which typically will be more than enough to level out you TV. But since the air volume of the springs is small, accidently letting out just a small amount of air while checking the pressure can make several pounds difference in the actual pressure. Additionally, you have to get both springs fairly close to the same PSI. Accomplishing this can easily take 5 minutes of fooling around. And, of course, the PSI changes with temperature by as much as several PSI. Keeping things just right is somewhat of a pain in the ----. But they do provide the needed leveling, and with a good digital pressure guage, a hand pump, and a little practice, things work just fine. And last, but not least, most of the time the TV is already over its GVWR and adding more suspension to level it out does nothing to help this problem, and most 3/4 ton TV's have a max rear axle rating of around 6,000# with upwards of 3,000# already being used up with the weight of the empty TV. For example, my 2500HD can handle only 2200# before exceeding GVWR, and approximately 2900# pin weight before I exceed the 6,000# rear axle rating.