Powerdude wrote:
On the 4 corner coil suspension technically there is no load bearing axle, just the spring in the coil is the load bearing part, and the frame of the vehicle with the control arms.
So, if you put an airbag to support the coil and the weight, your only limit is the tires and the strength of the suspension arm/bushings.
I'm sure he will have wearing and maintenance problems with that setup at some point. Hopefully no catastrophic failures at speed.
Coils or leafs the axle itself wouldn't be able to tell - as far as it's concerned the same forces are acting on its spring pad. Even bearings aside, the axle tube would feel additional bending moment regardless of spring type.
Think about it this way - semis use air springs not much different than coils. If the coil sprung axles are not load bearing then we should be able to put 1/2 ton axles on a heavy spec Kenworth!