I have a 34' TT gross weight 11,000 lbs. I am interested in keeping this unit long term and would like to put some kind of air suspension on it. I've read about trailair centerpoint, the kelderman system, as well as dexter axles air suspension.

I would like some real world feedback if you or any of your camping buddies use these systems. I'm also interested in hearing if any of you have fabbed up your own system. I'm not afraid to manufacture something myself, just looking for good feedback on what works well and what doesn't.

Thanks

Brian

 

Post the site your are looking at.... I am interested in this as well.

OG

 

Sure:

http://www.trailair.com/products/centerpoint/

http://www.keldermanairride.com/prod...?id=LEAFSPRING

http://www.dexteraxle.com/airflex_suspension

 

Those look a lot easier to build than the air hitch that I am building now... That took me a while to get my head wrapped around it...
I'll tell you that after seeing the destruction that I trailer can take with daily use trying to take it easy on it... Little things like airhitch and air ride suspension can make a big difference in the life of the trailer....
After looking at the different styles... I bet I could come up with a hybrid design that would be as good and easy to build... Let me finish my hitch and I will work on that.

Oilguy

 

Have you got any pictures of the hitch you're building? I'm interested to see it.

 

Not yet but I am working on it tomorrow... I will get some and post them... I am waiting for one part to be delivered and I can complete it. I can't wait to get it on the truck and try it out.
I am using the air hitch technologies design and made a couple of mods to make it work better... It has a 10" face and by their design it was going to need a 5" drop after that... I adjusted the receiver placement and solved the problem in the design side....
I should have been and engineer... I hate seeing a product and then seeing how it can be better and having to prove it to myself....

BTW... I drew out the design I though of when I saw the ideas for the air suspension... I will scale it and see if it still works and post it.

OG

 

That sounds great....I look forward to seeing it.

 

I looked at all the options and decided to fab one up loosely following the design of a hendrickson air ride, or airliner suspension used on large trucks. A friend had a tandem axle car hauler he wanted to convert to air ride so we used this a "test" mule and built an air ride system using a firestone 6401 bag on each wheel, with the idea of converting our RV's to air ride after.

The system worked very well on the car hauler so I am in the middle of fabbing up a complete air ride suspension for my TT. This invovles complete removal of the leaf spring system. I will post pictures of it soon for those who might be interested in building their own trailer air suspension.

Brian

 

That sounds cool... That is similar to what I drew up... I drew up a system that has one arm going forward and one going toward the back. I have a modified A arm design to prevent the axles from flexing the arms while turning and wearing out the mounting bolts or bushings.. The other thing I did is design the whole setup to be build and assembled off the trailer and then set the trailer onto is and attach it... That way you can get the right weight distribution and look you are going for.... I am going to use 4" drop axles on mine also to lower the center of gravity and cut down on the wind resistance a bit...
I would love to see pictures....
Take some during construction also!

Oilguy

 

Cool idea with the A-Arm. I am just using a transverse torque arm to take care of that force.

I will take some pictures of the unit on the bench before I install it as well as some installed photos.

 

I was looking at the schematics for the air line routing and noticed a tee in the system to allow one Schrader valve to service both air bags rather than one valve for each side. I realize that that is pretty much accepted practice with air shock helpers, air bags, etc. on the towing vehicles too. But it seems like, for instance, if you load one side of a vehicle, as in a turn, the air bladder on the outside of the curve will transmit the increased air pressure to the other side which will make the vehicle lean even more. If the bladders are isolated from each other then the pressure transfer won't occur and the vehicle's lean to the outside will be reduced ...... Right? Or have I just stayed up too late?

 

I've got my air suspension system installed as of yesterday, just a few finishing touches today. I'll post some pics of the project soon.

 

I see your point and logically it seem like a valid concern... I really never considered it before but it makes sense.
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I guess a lot of weight/pressure transfer would have to do with airline size and duration of the corner...

...

I was planning on hooking all 4 bags together but now I am rethinking it... Great .... Thanks a lot mj007!

OG

 

Definitely hook each bag up to its own line and valve for the very reason listed above.

 

Okay...I finished the project. The new suspension works very well. Test towing revealed that you could feel the cracks or pavement height changes as the wheels of the truck went over them but the trailer travelling over the bumps could not be felt in the truck.

Here is a bit of a progression of photos throughout the suspension changes:


First had to remove the old suspension by grinding the welds off.




Then I built some walking beams in a jig for uniformity, here they are laid on the floor to give you an idea how they will look:




I built the suspension on the bench so I wouldn't have to do any excessive welding under the trailer. It's obviously positioned upside down on the bench:




Here is the main beam welded into position and the axles clamped to the walking beams:




Here are the airbags and shocks installed:




Transverse torque arms installed to handle the side to side forces. These are adjustable heim joint arms:



This was a fairly labour intensive job taking about 20 hours from start to finish with a few breaks here and there but I think it will really help prolong the life of the travel trailer. After test towing it I'm satisfied with the results. I'll post some long term info after the towing season is over here. Now to consider what to do about an air hitch and have the trailer completely riding on air.