Does anyone have any specific experience with towing a large travel trailer with a weight distribution (WD) hitch setup and Firestone Air Bags.

I have an 08 2500HD Chev Duramax and tow a 32' TT which weights about 12,000lbs fully loaded. I have a complete 17,000lb hitch and WD system with Dual Cam sway controls. The WD bars are also 1,700lbs.

I have replaced the stock shock absorbers on the truck with aftermarket Bilstein shocks and still have some pitching going on over certain road conditions. Pitching results in the front of the trailer going up and down and consequently the rear of the truck goes up and down as well.

While I know the trailer will never be as stable in this regard v. a 5th wheel trailer I wonder about adding air bags to reduce (I know I will not be able to eliminate it) this pitching motion.

I do not have a truck sagging problem as is typical with the use of air bags. I am happy to invest in the air bags if they would be successful but don't want to waste my money.

I am trying to find some people who may have used air bags with a travel trailer and can offer some specific feedback as to the success or not of using them.

Thanks

It may help with the downward motion, but it won't with the upward motion, and in fact may make it worse. Airbags can't do much for dampening as they aren't designed to do that. Their primary benefit is raising the tow vehicle height back to normal when a load is out on it. Maybe a second set of shocks would help?

I just got done adding a set of airlift airbags to my 2500hd. I have a toy hauler 5th wheel, and my truck wouldn't sit level with the trailer attached. I kept getting bright lighted, people thought I was driving with my high beams on. I added the airbags and now the truck sits as level as I want it to. I used to get a lot of "springy" feeling over certain bumps and roads/bridges. All that is pretty much gone away with just putting in the airbags. Don't go spend $600-$800 on a brand new set, look on craigslist in your area. I found mine for $150 from a guy who got hit by a drunk driver and totaled his truck. I got the bags, all wiring, onboard compressor and all bracketry required. All I had to buy was about $5 worth of 1/4" tubing. The compressor is quiet and works great. These trucks technically should be able to do almost anything you want without airbags, but these gm's seem to be sprung pretty light in the rear. I was shocked that with my empy 5th wheel the truck would not sit level(something it was designed for). Just get the airbags and your truck will feel 100% more stable. Hope this helps.

I just went thru this after getting a new tow vehicle and setting up the old hitch for the new truck from our 1/2 ton suburban.
Since you have such large spring bars, and a truck with a HD suspension, you are probably putting too much tension on the spring bars giving you the hobby horse ride.
I ended up dropping my L brackets (I have an Equal-I-zer) trunion style WD hitch. I tried one notch and still had some issues, so I dropped it another notch and it it almost completely gone now...
Figure out what your tongue weitght is on your TT. I think you have the bars too tight...for a HD suspension.
You will never get rid of the undulations completely, but you can cut down on their frequency and duration...

I just went thru this after getting a new tow vehicle and setting up the old hitch for the new truck from our 1/2 ton suburban.
Since you have such large spring bars, and a truck with a HD suspension, you are probably putting too much tension on the spring bars giving you the hobby horse ride.
I ended up dropping my L brackets (I have an Equal-I-zer) trunion style WD hitch. I tried one notch and still had some issues, so I dropped it another notch and it it almost completely gone now...
Figure out what your tongue weitght is on your TT. I think you have the bars too tight...for a HD suspension.
You will never get rid of the undulations completely, but you can cut down on their frequency and duration...

Beat me to it. Great advice.

Thanks I try....

Bag it!!! You will love it! You will find some roads require more air and others less.

My truck does that even with the air bags, but it only happens on pretty bad dips on the road. I mainly have the air bags for when we take the golf cart with us. I agree with Tom S, so I honestly don't think it will help that much. I do need to get some new shocks in the rear.

I think DanielT is spot on with his response. I, too, tow a heavy TT with an equilizer hitch and had to back off my weight distribution (dropping my L brackets) because my ride was like a hobby horse on rough concrete highways.

Let us know how it tows after giving it a test.


Good luck

I just went thru this after getting a new tow vehicle and setting up the old hitch for the new truck from our 1/2 ton suburban.
Since you have such large spring bars, and a truck with a HD suspension, you are probably putting too much tension on the spring bars giving you the hobby horse ride.
I ended up dropping my L brackets (I have an Equal-I-zer) trunion style WD hitch. I tried one notch and still had some issues, so I dropped it another notch and it it almost completely gone now...
Figure out what your tongue weitght is on your TT. I think you have the bars too tight...for a HD suspension.
You will never get rid of the undulations completely, but you can cut down on their frequency and duration...

I apologise to all as I lost this thread as I am a bit inexperienced at these forums. I thought I would get an email when there were new posts but have not figured out how to do this. Thank you for your patience.

DanielT I have tried various spring bar settings as well as towing without the bars at all. The tonque weight is 1250lb loaded but not very wet. Not sure what the result would be with full tanks.

I find it worst over rougher roads in Mexico as their roads are not good as they are not particularly flat with constant undulations that make the pitching motion very bad sometimes.

When I reduce the spring bar tension the truck does not settle a great deal as the rear axel springs can carry the weight. What happens with light spring bar tensions is that the truck gets a very harsh choppy feel to it and you feel like you are driving a truck with no suspension. It is so choppy that it is hard to have a conversation as you sound like you are being beaten on your chest while talking.

I suspect that full spring abr tension does not allow the rear truck springs to engage fully and too light a tension and the trailers stiff frame transmitts all its jiggling straight through to the truck. I also wonder if adding shocks on the trailer might help, although the trailer looks like it travels very smoothly and does not visibly move around or jump up and down like I have seen with some 5th wheels.

After try many things am at a bit of a loss and ready to try some more drastic options.:(

your spring bar settings are not the only adjustment...hitch head (ball) height, and hitch head angle are all items that effect how the bars work, how the WD is effected and how much of the load is carried by the truck suspension.
On my hitch I have a draw bar with at least 5 holes for height adjustment, also have a tab that effects the hitch head angle relative to the draw bar and trailer frame, which effects the angle of attack for the spring bars.
I do not think air bags are going to solve your problem....possibly HD Bilstein rear shocks or double shocks on the rear. Sounds like with your setup, you might need some extra rebound dampening.

bags are very nice when towing heavy. they will not cure your problem but will help. look around...they an be found for a few hundred as opposed to 600 or 800 as stated before. good luck and let us know what you decide to do.

I have spent a lot of effort getting everything setup as close to perfectly as possible. Ball height is right. Bars are close to parallel. Trailer runs level. Have installed Dual Cam Anti Sway controls (does not affect pitching just sway).

As I said in my original post I have replaced both front and rear shocks with Bilstein already. The ride is much better unloaded and loaded with the Bilsteins so would recommend anyone to put them on. The pitching is much better with the Bilsteins as the front end is controlled much more than the stock ones. I always felt the front end was too soft and bounced to much both on the road and was very evident over speed bumps in parking lots.

I know bags will not solve all of this pitching but am wondering if in certain circumstances over uneven roads I can pump up a little harder and reduce some of this pitching from begining the wild ride that can occur. I am also concerned as you guys are that it could make it more bouncy so that is a concern. So was hopeing to find someone with realtime experience to provide their experiences.

I heard of a guy who owned a trailer manufacturing company (farming type trailers) who always removed his rear springs and just had links and air bags for all towing applications and swore by this setup.

Sounds like with your setup, you might need some extra rebound dampening.

Are stock bolt on brackets available to add extra shocks or is this a custom fabrication situation. I have no experience with lifting or modifying suspension stuff.

most of the poor ride is the overloads barely coming in comtact with their pads, bounceing off them, and sending the truck shooting up, the main springs not being able to support the truck 1 or 2 inches higher then normal, and the rear end falling back onto the overload pads, usually as the road comes up just enough to move the axle up as the frame is moving down, and off you bouce again.

Airbags to raise the rear end an inch or two can do wonders. The key is to either be completely on the overlaod pads, or well clear of them. this is the upper overload on the 3500's, and the bottom overload leaf on all trucks. A link setup with airbags and expansion tanks eliminates this problem. For the rest of us airbags, and maybe an expansion tank (the expansion tank reduces the change in spring rate of the airbags as they compress and stretch out, without changing the weight cap of the bag) is far cheaper.

http://www.keldermanairride.com/standard/truck/

most of the poor ride is the overloads barely coming in comtact with their pads, bounceing off them, and sending the truck shooting up, the main springs not being able to support the truck 1 or 2 inches higher then normal, and the rear end falling back onto the overload pads, usually as the road comes up just enough to move the axle up as the frame is moving down, and off you bouce again.


This sounds like exactly my problem. If I setup the spring bars to properly carry the load the trucks springs are not really engaged and there is this loading and unloading of the rear truck springs which seems to create the bouncing up and down cycle. Use less spring bar and the truck springs become fully engaged but the ride quality is really hard at this point. Just tough to find a balance that works to prevent bounce and still provide a reasonably comfortable ride.

hey

the way you can setup the hitch is the following :

mesure the opening of the hole (to the ball of the trailer)

make sure the trailer is perfectly leveled (front to back)

take mesures of where the ball should be from the bottom of the opening the hole of the trailer and make that measure to the bottom of the ball of the hitch

next attach springs bars with a minimum of 5 liks showing to ensure that thay can move while turning

and yeah the washers can do a lot of the angle of the ball you might wonna lokke at this to fine tune for the propser height

than put on the bars - they should be or parallel or point down, never up

before, take mesurements of the the height of your truck (front and back) without that trailer and it should not move a lot like half and inch is acceptable

write me back on this if it was helpfull

ps : I have a 20 foot travael trailer flatbed with WDH and air ride suspension at 10-12 psi and i works prwetty good and I am now at 105 000 kms and the ride is good like its not bouncing hard :)

my trailer is rated for 10 025 lbs maximum weight (2 axles of 5000 pounds)

take a look at this :)

this helped me a lot

http://www.youtube.com/watch?v=WTQ5ML-O4B0

http://www.youtube.com/watch?v=lnV9T0WEjAA&feature=related