I had the firestone ride-rite dual bellow air springs. I hated them, and am now going to give them away. I'd try to sell them, but they are so cruddy, I'd never feel right taking money for them. I took them off because they made the truck ride like crap. I posted this in another thread:
I put some of those on my old truck. I hated them. Jack the back of your truck up until there is no weight from the truck on the axle. Then measure the distance between the rubber bumper and the stop on the axle. This is the total amount of travel that your rear springs have. The greater this distance, and the more your truck uses when sitting (until it hits the stop), the better it will ride.
You will most likely come up with a measurement of 8-9 inches. Now fully compress one of those bags, and measure how tall it is. Then let the air back into it and measure how tall it is as it sits on a table or something. That is the total travel of the bag.
OK, I just went up in the attic and got one of them because I wanted to see if they were as bad as I remembered.
Not including the studs, it is 6" tall when just sitting there.
When fully compressed, (with my sister standing on it) it is exactly 3" tall. That means it has about 3" of total travel.
3" isn't much compared to stock, and some complain about how the truck rides stock. In reality, they really don't have that much travel. The pressure inside the bag goes up exponentially with respect to how far the bag is compressed. So unless you have an active reservoir (which I did in an effort to make these things not suck), the bag will never fully compress, making the actual useable travel about 2. 5 inches. Needless to say, my truck was very miserable to drive with those on it, thus they are sitting in the attic, and my old truck had useless holes drilled in the frame above the wheels.
There is one good use I could see for them. They would make the ultimate bump stop, like a replacement for the rubber thing on the frame. Their exponentially progressive increase in resistance to load pressure would make them perfect for this.
Even with no air, they are still limiting your total travel to 3 or less inches, and the truck will ride much worse, and if you hit any speed bumps at speed, you will bend the mounts or the frame if you're unlucky enough.
These are just my experiences and observations. Not discourage you, but I would never put those on any truck ever again.
At least I can tell you what ones NOT to get!
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