I just loaded a new-to-me Lance 990 slide-in camper on my '03 2WD Quad Dually 3500 and the 2930 pound camper compresses the springs to where there is only 1.25" before the axle tube contacts the factory rubber bumpers on the frame.

The smallest bumps (even on an Interstate) cause the suspension to bottom, making the combination pitch and buck badly.

I am looking for the best supplemental suspension aids that will retain the stock ride the best w/ the camper not installed, yet which will provide adequate support and suspension travel for my camper.

The choices are:
1) Air Bags: http://www.suspensionconnection.com/...on/6216D2.html
2) Supplemental Springs: http://www.supersprings.com/Applicat...0HD_cab_ch.JPG
3) Timbrens : http://www.timbren.com/timbren-appli...s/DR3500CA.pdf

Thanks-
Bob

 

The air bags will help you carry the load and are adjustable to how much load carrying capacity you need. I had the same issue and these took care of the problem. I have the Firestones. The Hellwigs look like they may use Firestone bags. Firestones are probably the most common air bag and will most likely be the easiest to get parts for if you do need them. I have run mine 4 years and 40,000 miles with no problems. Most over the road trucks class 8 trucks here in the US run Firestone airbags as OE equipment.

 

How much loss-of-ride-quality when empty, and the bags are at minimum pressure did you notice?

Bob

 

i have pacbrake bags and dont notice any real change in the ride unloaded with 5 psi in the bags.

 

I see the PacBrake model for my vehicle mounts just like the Hellwig bags* (over the axle, not outside the frame), which is what I want.

What features influenced you to get the PacBrake brand?

I want to get the most for my money-
Bob

* http://www.suspensionconnection.com/...on/6216D2.html

 

Hi Bob;

Lance is a very nice truck camper, but the weight and dynamic CG does require ... assistance .. as you have noticed.

I would go with airbags & a rear torsion (sway) bar. That will give you the better loaded versus unloaded ride quality plus let you maintain the same ride height loaded & unloaded.
I actually found my unloaded ride was better with the airbags at the 5 psi

I haven't looked at the Helwig bags, but the biggest difference between the Pacbrake & Firestone bags is the aluminum versus steel end caps. All brands of airbags are quality products. You need to decide which features are important.
Due to spring dynamics, I feel airbags mounted inside the spring pack is best. You want the leaf springs and (supplemental) airbags to work together.

 

air bags

 

Thanks-

Firestones are by far the cheapest, and here in TX, corrosion (rust) isn't a problem (so the steel end caps should be OK). Plus I see for the Dodge (unlike the Ford) even Firestones mount inboard of the springs and frame, so no drilling or offset air bag bracket is necessary.

The Firestones will probably get the nod, then, on price alone.

I thought the truck actually handled fine w/ the camper (and no sway bar), but then maybe the outside suspension was bottoming on the frame bump stop in turns, increasing the roll-stiffness. Maybe when I raise the suspension, sway will become a problem.

In any case, I think I will go the air bag route and then see what else I might need to do.

Thanks-
Bob

 

Bob;
I used a wrong word in my earlier post. I feel the best airbag mounting is WITH the spring pack meaning it mounts inside the spring to spring perch. The bag manufacturers have done their own research and determined the better installation method so back to what you want.
Do plumb the bags separate. Many shops will suggest a common fill, but that only applies to 5th wheel (gooseneck) or bumper pull. A TC needs the separate control in the bags to prevent an added roll.

Speaking of controls, I do not have an onboard fill system. I adjust my pressure with a $5 bicycle pump.

Do plan on a swaybar, sooner versus later.

 

Is this because the bag on the "outside" of a turn will transfer air to the inside one accentuating the "lean" of he truck if they are connected together?

 

Yes
I normally run 5-10 psi higher in the curb side bag to help with road crown, too

 

Interesting. Do you find that this makes a noticeable difference in handling? My Lance puts the potable water and waste water on the driver's side, though I don't know the left/right weight distribution otherwise. The 3400 watt generator's on the passenger side.

Bob

 

The Pacbrake hardware appears stouter than the Firestones and they use two u bolts to attach the lower plate to the axle.

 

A real cost effective way to control sway and forward pitch is to install Rancho 9000's. They're adjustable for the load. They're easy to adjust so I wouldn't waste money adding the in dash fill system. Mine took maybe a minute to do all four.

 

I do like the Rancho 9000's on my 1st Gen from an adjustability standpoint. There was an issue with the springs whereby the driver front Skyjacker was sagging quicker than the others. I was able to offset that by adding a leaf and a 1" block on the opposite corner to level it out. Unfortunately that also introduced some off-kilter unpleasantness to the handling over road irregularities at speed. I corrected that anomaly by simply turning down the stiff corners and turning up the soft corners with the Ranchos. Worked perfect.