Air bags on the rear suspension?
 

Since Many Semi's have logged millions of miles with airbags on their trucks has anybody (i did a quick search on this for this on this forum), added these to improve their ride in the rear of the truck? I have ZERO interest in "laying frame", on this truck or even "C" notching the frame in the rear.

Basically here's what I have, a 1973 GMC Camper Special 3/4 ton (2wd), and I would like to improve the ride (especially in the rear). Since I have no plans to ever load this truck down again with a Camper and a Boat, I am thinking of placing some heavy duty air bags back there to improve the ride, yet also have the ability to carry a heavy load if needed.

Since I have gotten this truck (some 4 years ago), it has seen ZERO heavy load carrying. So going forward it will be mostly pleasure ride.

Thoughts?

Re: Air bags on the rear suspension?
 

A 4 link would be most ideal for ride, and capacity.

I went with a air over leaf set up on my C10 since I be poor. Still dialing it in, but the ride is better then before. I used 3 leaves from the old pack of 6, and Slam specialties SS7 bags. I should get rid of the mid spring, but i will see how it does when inlower the front. They are mounted in a bag over axle style. I would recommend 7 or 8 inch bags even for helper bags as they ride better then the 5 or 6 inch variety when you just need a little help. I am using Schrader valves mounted to the bumper, and a foot pump to change pressure.

Currently I am running 20psi in both bags to level the front, and back out. I really need to swap my front cradle to lower the front so I can lower the air pressure for better ride. When I did my new bed wood. I had to flip the axle, and shackle for proper clearance. On my C notches I used Amazon special 2018 Silverado rear bump stops for a softer bottoming out.

I would say the ride vs my old ride is quite improved right now. Even though it is still in a comprised setting. Combined with my broken seat back making things worse. My old leaf set up was the HD 56" pack for a C10. Which explains why I have the 12 bolt in my truck vs the common 10 bolt.

Re: Air bags on the rear suspension?
 

Changing the factory HD leaf set-up for something lighter duty will yield a difference. Which option/path you choose has different costs & effectiveness. How invasive of a project are you wanting? This is how I would imagine the ladder of effort involved:

A lighter duty leaf pack from a later model truck could be a possibility.
There are also leaf spring manufacturers that I've seen/read about offering 'soft-ride' options for lifted trucks. I'm betting there are possibly some options there that might work.

Removing the HD leafs from the current spring pack & adding an air-over-leaf sleeved bag set-up. This offers adjustability but fewer leafs = less axle wrap control (I don't think it would be an issue here, but it should be mentioned).

Removing the leaf set-up & going to a full 4-bar link system w/air bags would yield the most improvement in ride quality & the best rear axle control. BIG difference in ride quality vs a stock HD leaf set-up.

My dually has the 4-bar/rolling sleeve bag set-up. Ride is leaps & bounds better vs the 13 total leaf set-up it replaced.

Yes, mine is lowered but I planned/built it that way. It also could have been set-up for a stock height.

Re: Air bags on the rear suspension?
 

I used the sleeve type on my blazer, AOL style Firestone 9000 I believe. Not that harsh of a ride

Re: Air bags on the rear suspension?
 

Before changing springs, remove the shocks and see how easily you can compress the rear springs. The rear of my '66 floated and could easily be compressed 3-4" with the shocks removed. It may be that it has very tightly valved shocks that aren't allowing the suspension to compress/extend easily enough over bumps unless there is added weight in the back. You might be able to get away with lighter duty shocks and your current springs.

Re: Air bags on the rear suspension?
 

Good point & an easy thing to try.

Re: Air bags on the rear suspension?
 

Thanks for the ideas. This Truck is so stiff you have to put a ton of weight in it to bring the rear down any. When it had the overhead pickup camper in the truck we were always surprised how little the bed sank when the Camper was place in the bed, then we added the tong weight of the boat and it might have sank 1", total.

The leaf springs on this truck are literally 2-3" thick in the amount of leaves stacked upon each other!

Re: Air bags on the rear suspension?
 

Sounds like a definite candidate for a lighter duty leaf pack @ this point. Helper bags can be added if needed for any occasional added payload needs.

Re: Air bags on the rear suspension?
 

Here's a couple photos of the springs and how thick they are!

Re: Air bags on the rear suspension?
 

I like the idea. I used to own an 83 GMC Camper Special that was used occasionally for pulling a trailer. Other than that it was just a daily driver. I thought about going to 1/2 ton springs and bag over axle. Then if I needed to tow I would air up the bags to help with the load.
I never got around to it. I am sure that there are a lot of other options that one could go with.

Re: Air bags on the rear suspension?
 

There are several Air-over-Leaf set-ups that are bolt-on friendly. No need to do a more complicated bag over axle install here. Keep it simple w/a lighter duty leaf pack & A-O-L set-up.