Some time ago I put some airbags
in my '03 Suburban '1500 (rear coil springs) to help with heavy loads. Since this was pre-AS, I actually did it because I bottomed out on bump stops one time when I loaded up with friends and gear.
They work quite well when loaded and really help with sagging while towing the AS.
The problem with these are that 95% of the time, when you're not loaded, your ride is crap, as you minimally must keep 5psi in the bags. I know 5psi doesn't sound like much, but it feels much like an unloaded 2500 pick/up now.
I've been researching other solutions. I was really looking for a solution that removed the coil spring completely and replaced with an airbag as I'm sure that would handle the rough ride when empty, but have had no luck. (and would still prefer this option )
In my research I found this company, Timbren
. This company uses a progressive sort of bump stop that supposidly doesn't activate until your loaded up. Haven't been able to get a price yet but they seem that they would be quite inexpensive.
Will try them shortly if I don't hear anything too negative here, or don't find an airbag replacement for the coil.
Thanks for all suggestions.