Ford built some of the Gen 2 F-150's and Expeditions with an air suspension system that, at least in the shop manual, looks like it might go right on a Lightning. It appears to have an air bag right over the axle, along with a single leaf spring and a traction bar running from the forward spring mount to the bottom of the axle tube.

The manual says "The air suspension system is designed to improve ride, handling and general vehicle performance." Hmmm, sounds good to me!

It looks like it might improve the traction without hurting the ride, as well as making ride height adjustable at the twist of a ****.

Has anyone done the swap or know if it can be done?

 

I guess that my first question would be why, when you can get aftermarket helper bags for less than $200 ($200 more for cab-adjustable)?

I mean, it's an interesting subject, and I'd like to see the answer, but it does not seem like the economics are there.

 

Tim you got a link to these bags?

 

I've installed AirLift helper bags on several vehicles in my checkered past. They are great for propping up inadequate suspension, but what got my interest was really the combination of traction bars and variable rate suspension. In the realm of air springs, such as those on buses and trucks, the bag is basically a doughnut shape sitting on various shaped cones. As the cone shape varies, so does the rate of change in suspension stiffness. A relatively pointed cone gives less rate increase and a flatter cone gives a higher rate increase. Give me a good rising rate suspension, (high taper, fairing to flat on the theoretical cone)coupled with no pinion climb, because the system includes traction bars, and I'm really an interested party. Leaf springs, for all their simplicity, still go "S" shaped on acceleration, resulting in less than desirable pinion angles. Pinion snubbers are not the solution for the problem.

 

Oh, one more comment.....

Tim, I find no relationship between economics and going fast. One is a very boring major and the other is just plain fun!!

 

http://www.airliftcompany.com/slamair.htm

 

Is this what you are talking about?

I don't see any leaf springs.

It also does not appear to me that the frame is quite the same, so I don't know what work would be required to mount all this stuff up.

Finally, where are the shocks? Maybe inside the airbags? Or just ahead of the bags?

 

Looks like the shocks are in front of the bags..

 

look at those suspension bars? they look kinda like traction bars

 

The 1999 1/2 Lightning shop manual supplement had a markedly different illustration. I have the manual at work, so I'll scan the diagram and post it on Monday. The illustration that Tim posted shows lower control arms and a panhard rod, but I don't see any upper control arms or a torque arm (ala Camaro) to keep the rear end from rotating around the axles. A true four link setup would have arms above and below the axle tube so the axle would swing in an arc about the instant center created by the forward pivot points of the control arms. The Ford ilustration I've got shows what appears to be a monoleaf rear spring with a traction bar tied to the bottom of the forward spring mount running back to a tie point below the axle. Using the monoleaf spring avoids the need for a panhard rod and allows the axle to travel in a more vertical path without huge changes in the pinion angle. If the illustration is anything like the actual setup, everything should bolt on with no frame surgery required other than replacing the forward spring brackets. I'll take the book to the local dealer and see what really exists.

 

I did considerable research on the air bags after I got my 99 L.

I have the airlift brand bags on my Diesel 4X4 and was able to eliminate the helper spring on the stock leaves. It is truely the answer for someone who wants the tuneable suspension.
A rancho 9000 adjustable shock and the airlift kit allows you to firm and level it up while towing and soften it for empty driving.

So, getting back to the 99 L with 800 pound payload I figured it was the answer. Every where I checked they had it for the F-150 and some folks had claimed to put it on a lighting but because the L is lower than the two wheel drive version the brackets would always hit or you lost the travel and were not in the demension called out by the manufator for operating range.

I went to several trailer companies in town that do set ups and they said they could make something work but didn't recomend it.

I finally dropped the idea because it fit between frame and axel and I didn't want to hack something in.

Back in the 70's my Dad and I both got these air shocks for the rear. He got them for his Ford Galaxie 500 for towing and I wanted them for Jacking up the back of my 67 Mustang. They worked great!!! But over the years lost popularity. I think someone makes something but getting the length right for our trucks would be unlikely since they weren't ment for really hard use and Valve dampening wasn't an option.