Suspension help
So I have a 2013 GMC 1 ton doolie pulling a very heavy 44 ft Road Warrior toy hauler. I added the Firestone air bag system a while back to compensate. Without it, my truck will sit on the overload...
Forum Discussion
Cummins12V98 wrote:
Wes, that's impressive!
I just know I had an onboard in cab pressure gage that I could air up and down each bag. At 5psi unloaded when the RV was added the pressure went to 30psi.
No math formula need for me just visual proof.
That is why I always ask people if the air pressure they are referring to is loaded of unloaded. Still I don't understand why tires are not affected in the same way.
I figured this would be pretty easy to verify so I did.
Aired both bags (new one on passenger side) to 50 psi
Hooked up trailer and measured again. 65 psi
Why don't tires show this dramatic change in static pressure under load? My opinion is because they are bigger and there are 4 (or 6) to spread the weight.
Now, under dynamic road conditions, the 2 bags are taking a lot more force than the 6 tires, plus you have the suspension absorbing some of that as well. That's my layman's take.
I also verified the max PSI for the bags is 100 psi, not 80
