PacBrake airbags…….maybe I made a mistake

[Dreamer]

I'll try, here's a pic I just took from my phone, kinda dark

JJPage, thanks for the photo. That helps put it into perspective. Did you have to do anything to keep the square tubing from twisting or turning sideways?

 

[Bill Stockard]

I keep going back and forth on the bump stop mod, I think it would be great when loaded but I am not sure how well it would work unloaded on bump roads.

My bump stops don't contact the spring at all unloaded, The Timbrens will contact the axle first. The bump stops contact the springs only when the 4,000-lb truck camper is loaded and the Timbrens are compressed. I don't know what the spring rate is on a 3500 SRW and don't know if the bump stops would contact when unloaded. For towing a travel trailer like yours, I wouldn't bother with the taller bump stops.

Bill

 

[JJPage]

I keep going back and forth on the bump stop mod, I think it would be great when loaded but I am not sure how well it would work unloaded on bump roads.

When unloaded, are you sure the bump stops would ever come on contact with the overload spring? Seems unlikely.

It wouldn't take much suspension cycling to contact at all, probably not too much around town but on back roads I wouldn't be shocked at all.

JJPage, thanks for the photo. That helps put it into perspective. Did you have to do anything to keep the square tubing from twisting or turning sideways?

When unloaded the overloads do engage once in a while, like a speed bump at Home Depot, and it gives quite a kick, especially to those in the backseat. But if I keep at least 15# in the bags it's not a problem. You could also experiment with different size tubing 1 3/4", 2 1/4" etc till you get it right for your application.

Dreamer, I didn't have to do anything special to keep from twisting, hasn't been an issue, I just cut the 2" tubing in 3" lengths to match the existing frame and pads and all is well.

Jess

 

[Dreamer]

Picked up the camper for the first time and headed home. The former owner has the same truck and suggested 30/35 lbs psi in the air bags. It felt ilke I was very wobbly and unstable. I noticed the overloads were not touching the bump stops. I then adjusted the air down to 10 psi and that seemed to stabilize the truck some. I now wonder why I bothered with the airbags and am thinking of removing them and selling them. If I add something like stable loads or spacers to engage the overloads earlier plus a rear sway bar, it seems that I would gain what I am looking for. Better levelling when loaded with a heavy camper and less sway. Does this make sense?

 

[AH64ID]

I am surprised it didn't lower the truck more.

I would wait to pull them until you get the camper loaded, you weight will probably go up quite a bit. My dad's 2600lb camper, Lance published weight, weighs in at 3800-4000 lbs once loaded and on the truck. It takes 80-100 psi in the bags with his 2" level and 2500 springs, the DRW main leafs are only 7% stiffer.

 

[Bill Stockard]

If I add something like stable loads or spacers to engage the overloads earlier plus a rear sway bar, it seems that I would gain what I am looking for. Better levelling when loaded with a heavy camper and less sway. Does this make sense?

Yes, you are on the right track!! Taller bump stops and a rear anti-sway bar will help stabilize your truck-camper combination.
FYI:
http://www.torklift.com/products/stableload.php
http://www.hellwigproducts.com/products/sway-control/truck-suv-sway-bars/

Bill

 

[RBridenbaugh]

For the first couple of years I was happy with only the PacBrake Airbags and Torklift StableLoads for my 4,200 lbs TC on my dually (weight ready for camping, full water, propane and gear). Adjusted airbags to just engage the overloads. Little sway.

After changing out front ball joints I had some bump steer issues (definitely scary with the TC in the back) until they were worn in. To eliminate that induced sway I installed a RoadMaster rear anti-sway bar, and now have very little sway. No issues passing semi's, nor gusty side winds. The truck with the TC will never handle like a sports car, but drifting with the TC in the back is not something I want to do.

The air bags are still useful as the TC is heavier on one side than the other. They stop the heeling and level things out when driving in crosswinds. Once at a spot, after releasing the Fastgun tie downs, the air bags are used to level the TC (front to back and side to side). Keep your air bags and add the stable loads (or bump stop extension equivalent). If you are happy, you're done. If you are not, then add a big rear anti-sway bar.

By far the best change to my truck to handle the TC from a driving comfort point of view was the PacBrake Exhaust brake, not the suspension mods. Lots of steep, curvy grades on bad road surfaces where I go.

 

[Dreamer]

Thanks for sharing your experience. Maybe I will keep the airbags as they are on and working. I fully agree with the exhaust brake. I have the BD brake and love it. It adds a lot of comfort when heading down those steep grades with all that weight on the truck.

 

[Dreamer]

Just as an update on this subject, I followed the advice given here and installed 1 1/2" square tubing, 3 inches long as JJPage suggested. Now the overloads engage earlier and support the load and reduced the side to side sway. Unloaded, there is about 1 to 1 1/2" of space before the overloads contact. This does create the odd bump/clunk when going over train tracks or speed bumps but I can live with that. Total cost was $10 for tubing and $6.00 for bolts. I have new Bilsteins ordered and will put them on soon.