Air Lift "Primary Air" rear suspension

[DMAXTER]

Has anybody installed Air Lift's new full air suspension for the rear of 2500 and 3500 pickups? It completely replaces the leaf springs and comes complete with a large compressor and an automatic leveling system. For details see www.airliftcompany.com/PrimaryAir.htm (http://www.airliftcompany.com/PrimaryAir.htm) Air Lift's website indicates that it has been available since late May 2003.

[sonofagun]

Dmasxter,

Very interesting. Did you get any quotes for a 3500?

Thanks,
Bob

[DMAXTER]

I haven't called yet but their website indicates you can call 1-800-248-0892, ext. 244 for more information or to place an order.

[BlueOx03]

I just got off the phone with Brad, Great guy. He gave me a lot of info, hopefully I can remember and pass on the critical stuff.
The system was originally developed for an ambulance company and it was decided to release it to the public. The test mule for the GM platform was a 02 3500. The truck was a summer employees that was used frequently to pull a 5er full of Air Lift stuff to shows around the country. He racked up around 25,000 miles on the truck over the summer with the system on. The load leveling system is simplified by electronics. It kicks the pump on to fit the bags once they've been compressed 6% for over 20 seconds. The pressure is dropped via solenoid valves in the same manner. The time delay is to keep the system constantly inflating and deflating while on bumpy roads and such. He also recommended using the Rancho RS9000X shocks with the system for the best ride. The cost of the system is not for the meek, $1995.00. Sounds Like a good investment for those who spend a lot of time in their trucks. They recommend against the use of this system for altering ride height; it's designed to maintain factory ride height.
I know this was long and I probably left stuff out, but I hope it sheds some light on the subject.

TJ

[MadDuraMax]

Looks like an interesting system but very pricy. We were selling to OTR trailer manufacturers for around $1,000 per axle! The electronic valve is trick, but it's tough to beat the old pneumatic version that would resale for around $25.

Adding a second height control valve for two sided application seems like a good investment if you load the bed unevenly per their FAQ.

Not enough detail on the drawings to see exactly how the axle mounts to the trailing arm and frame, beware that solid mounts (verses rubber bushings) tend to break things much more easily.

Note: I engineered, installed and had to warrant these for OTR truck and trailer for nearly 16 years, so I tend to be over critical.

Mark

[moisheh]

I went to their web site. Sounds like it MIGHT be a good system, but pricey. $2000 for the parts, maybe 150 for the exhaust mod, if you dont install it yourself 10 hours at say $65.00. I also wonder if you lose the underslung tire carrier?

[Rick T]

This looks very similar to the Fleetco system installed on my truck. It's possible these designs were purchased from Fleetco. I've been very pleased with my system, although Fleetco having gone out of business 1 week after installation proved to be a problem when the German air bags proved faulty. Best I could do was get a free install of equivalent Fireston air springs.

These systems do provide a nearly level ride at all times and a much smoother ride empty or when towing a light trailer. A properly designed system maintains axle capacity, so don't expect too much difference when towing heavy.

I'm impressed with my Bilstein shocks, but might have considered an adjustable rear shock to really take advantage of the much reduced spring constant when unloaded.

The air springs are very tough gear, but I do carry a spare in my horse trailer. I'm going to look for a spare compressor, as well, but simple addition of a Schraeder valve to the air tank would permit airing up the springs from any pressure source.

This is an intriguing option that greatly improves the empty ride of the truck, but don't expect any electro-pneumatic system to be as reliable as iron springs.

Rick T

[mdadgar]

Kelderman Manufacturing builds a similar rear air suspension, which I have on my truck.

Kelderman Air Ride (http://www.keldermanmfg.com/new_air_ride.htm)

They also have a new 4-link rear air suspension that does away with the leaf springs entirely. It's only available for longbox trucks, unfortunately, so I couldn't use it.

I'm very happy with my Kelderman Air Ride setup. And they have, bar none, the best customer service I've ever experienced. The intial install was botched by a shop (that Kelderman referred me to, ironically) and Jeff Kelderman stood behind it every step of the way.

I'm sold.

- Mark

[Joe Pool]

StrangeEngine (Mark),

Is there enough room to store a 265/75R16 spare tire in the stock location with the Kelderman setup? I also have a Mag-Hytec cover which reduces forward clearance for the spare.
What do you think of the overall quality of the system and does the hitch portion bolt on to the rear bumper like the factory one?
Which type of air bags are used on the shortbed system; Rolling Lobe or Convoluted (Girdled)?
Did you have to modify your exhaust system at all?
I am very interested in their system for my '02 D/A CC SB as well as their front and rear system for my '02 CTD Ram.
Sorry for all of the questions, but actual owners are some of the best information sources.

Thanks in advance, Joe

[Joe Pool]

Rick T,

Do you by chance know the part number for the Firestone air bags used on your Fleetco system?

Thanks in advance, Joe

[mdadgar]

Originally posted by Joe Pool:

Is there enough room to store a 265/75R16 spare tire in the stock location with the Kelderman setup? I also have a Mag-Hytec cover which reduces forward clearance for the spare. The 265 tire is just over an inch larger in diameter than a 245. Given that, the 265 tire should fit. It'll be tight, but it should fit, even with your Mag-Hytec cover. I plan to use 265's on the truck at my next tire change, so I'll know for sure. Failing that, we could call Kelderman and ask.


What do you think of the overall quality of the system and does the hitch portion bolt on to the rear bumper like the factory one?The system is built very well. It does, in fact, bolt onto the rear bumper like the factory one. However, given the way that it bolts to the frame, it should put less stress on the bumper. All the welds look good and they used very solid components. I had one failure (a piece bent in use) and they replaced it with no questions asked, at their expense. The new piece will NOT bend, as it is one thick hunk of metal. A load heavy enough to bend it is going to bend the truck first.


Which type of air bags are used on the shortbed system; Rolling Lobe or Convoluted (Girdled)?I have absolutely no idea. Here's a pic (http://www.pdc-racing.net/gallery/misc/airbags.jpg) of one of the airbags. You tell me which it is.


Did you have to modify your exhaust system at all?No, I didn't. It clears just fine. Looks like there's plenty of room for a bigger exhaust, too.


I am very interested in their system for my '02 D/A CC SB as well as their front and rear system for my '02 CTD Ram. Sorry for all of the questions, but actual owners are some of the best information sources.No worries. Happy to help. I got the self-levelling option, which includes an air tank and a nice compressor. I had the compressor mounted to the rear face of the crossmember and the air tank mounted to the forward face. At some point, I'll probably add an air chuck to the tank so I can have compressed air at the track for my race car. It's not enough to run air tools, but it would be nice to have a source for adjusting tire pressures. The air tank pressure cycles between 85 psi and 105 psi, so it would be plenty.

One thing to keep in mind is that the suspension is very visible from the rear of the truck, as much of it is right under the rear bumper. That took some getting used to. Here's a picture (http://www.pdc-racing.net/gallery/misc/rearbumper.jpg) so you can see what I mean.

- Mark

[Joe Pool]

Mark,

Thanks for the great response.
The type of air bag is a Double-Convoluted style.
I'm still on the fence -- I'd prefer a system that uses Rolling-Lobe (piston) style air bags.
When you put your 265's on let me know if the spare fits.

THANKS AGAIN!
Joe

[mdadgar]

Joe,

You're welcome. Glad to help.

Now you've got me curious - what's the functional difference between the two styles of airbags? Why would you care?

Thanks.

- Mark

[Rick T]

Joe,
The Firestone air springs I installed on my Fleetco suspension are "8977's". There is a longer part number, but this designation is referenced in the Firestone air spring catalog (available gratis from Firestone). This is apparently a very common unit used on many full and partial air suspensions.

I was very fortunate that the German air springs crossed well into Firestone, as despite help from the US rep. for the German company, Phoenix AG, Phoenix air bags are simply not available in the US except for the speciality applications into which they have been designed.

Rick T

[Joe Pool]

Rick,

Thanks for the part number.

Joe

[wheeler]

Wondering if Primary Air might help me out? I tow a big 5er w/ 03' D/A 2500HD. Right now when loaded, rear of truck squats a bit and headlight aim was off; had considered adding AirLift bags to level out the rear. Seems Primary Air could do that...

But something else I'd really like to accomplish is improved empty ride of the truck. I typically unhook the fifth wheel, then drive around town for three days before I lash up and move on, so I pretty much keep 80 pounds of air in the truck's rear tires all the time. Wondering if even at 80 pounds of air in rear tires the current ride harshness would be dramatically improved with Primary Air and the recommended new shocks-- or if even with new air ride you'd need to let some air out of the rear tires in order to get a decent ride around town. Thanks for any feedback. --wheeler
(RV webpage: http://homepage.mac.com/gadgetnut/PhotoAlbum3.html