Suspension Airbags for Camping

[cgeggatt3]

Has anyone bought Suspension Airbags for their NV3500? Can’t find any that fit online! Thanks everyone.

[ASD Dad]

What do you mean by "camping"?  As in you have a camper conversion and the rear is sagging or the rear is sagging when towing?

 

It should not be sagging too much period if the load is correct either with raw weight you have in the conversion or with a properly setup weight distribution hitch.  If it is just sagging too much for aesthetics or comfort than an airbag may help.

 

Firestone used to make a set that would fit but were not a direct "3500" set.  I believe there is a company in Canada that makes a set that fits the 3500 out of the box.  

[cgeggatt3]

Thanks ASD DAD,

 

We see not sagging the back because we bought a camper (pulled behind) that is 6700lbs. Our NV can pull up to 8700, but I was just looking around to see if anyone had some sagging and used these suspension airbags in their NV, I just couldn’t find any that fit NVs. Thanks!

[cgeggatt3]

We are not sagging*

[ASD Dad]

Thanks ASD DAD,

 

We see not sagging the back because we bought a camper (pulled behind) that is 6700lbs. Our NV can pull up to 8700, but I was just looking around to see if anyone had some sagging and used these suspension airbags in their NV, I just couldn’t find any that fit NVs. Thanks!

 

So why do you want air bags?  You DO have a weight distribution hitch right?  That is required - period - for that weight camper.

 

Air bags are not cheap, can leak, can tear, require a compressor to inflate when needed since if you leave them inflated they will raise the rear with no load and will ride like a logging truck unless they are deflated.  You cant deflate fully since they can tear then as well.  They always need a little pressure in them.

[cgeggatt3]

Thank you. It appears I don’t need them ha I am very excited. Do you have any tips on must haves. This is our families first camper so we are learning and looking forward to making memories. Thanks guys!

[ASD Dad]

Pick a decent WD hitch from a good company- Reese, Blue Ox, Anderson, Curt, Husky, etc.  Then READ the instructions.  Do not depend on the dealer to install it correctly if they are doing it.  If they are including one it most likely a cheap basic model which is fine, they work, just dont have all the newest designs and ease of use.  Most cheap ones will have both spring bars for the WD part and a separate friction anti sway bar that attaches to the tongue of the camper.  They work.  They are also noisy and have more moving parts to keep track of vs. a newer design.

 

Pick a decent electric brake controller and mount it somewhere that is within easy reach in case of emergencies.  Also READ the instructions.  Most people never read anything and then cant figure out why their camper is towing bad or their tow vehicle is all over the road.  

 

Do your research, read reviews and read instructions and you'll be good.  You may want to find a big empty parking lot to practice backing up and maneuvering if this is your first time towing. 

 

Lastly and I honestly cant stress this enough 1000 times over - be overly OCD about your camper tires.  Most campers come with the cheapest tires possible and they have tendency to literally blow up if abused (or even not abused).  Always check tire pressures, always check condition and just take good care of them.  Always.  OR - take them off and swap them out to a better tire.  We do that on all our campers now as soon as they are home.  Seriously.  With zero miles on them.  After having dealt with blown tires in the past with the damage and delays they cause it is not worth leaving on the original tires.

[ducnut]

Airlift can probably help you with an airbag setup. Most of their kits are pretty generic, based on leaf width and distance from the leaf to a suitable mounting point on the framerail. If you measure leaf width and the distance from the top of the leaf to top and bottom of the framerail for a mounting bracket range, a tech should be able to come up with something.

 

Airlift’s auto-level kits come with everything you need for a user-friendly system. The compressor kicks on and fills the system, as needed. If you hardwire it into switched power, it’ll always maintain a minimum pressure in the bags, so they’re not wrinkled. I wired mine through a relay, so I can switch the system on/off, as needed. I tired of the system making sometimes unnecessary adjustments, like sitting in a drive-thru and on uneven pavement.

 

The kit includes a ride-height sensor that is easily adjusted for how you want the vehicle to sit. I’ve found my truck actually rides better with the system raising the rear ~1/4”, so the truck’s weight is being carried by the bags. The airbags do not make the ride harsher, in any way. In fact, under any load, my truck actually rides better than having the factory leaves mashed down. The bags keep the suspension up and off the harshness of the thicker, shorter leaf springs. Like any system that uses quick-connect fittings and plastic lines, there is some leakdown. But, it’s no worse than semi-trucks that use the same components.

 

Andersen make the absolute best, weight distribution hitch in the business. I have ~40K miles on mine and it’s as quiet and smooth as the day I installed it. I use the airbags to support the weight on the hitch and use the Andersen to stop the porpoising, which is the way a properly set up vehicle/trailer combo should be. Trying to use a WD hitch to compensate for inadequate suspension is incorrect. That creates a “bridge” between the steering and trailer axles, with the drive axle not having as much weight on it as it should, for the gross combined weight of the combination. I can tension my Andersen to the point where I can smoke my rear tires from stoplights, pulling a loaded trailer. Using a WD hitch like that in snow or rain is a jackknife looking for a place and time.

 

Maxxis offer the best of non-commercial trailer tires and are well known for their durability. They offer “D” and “E” load ranges in the two common trailer sizes and are inexpensive. Be sure your trailer tires are balanced, as that’ll help reduce fatigue on the tires, suspension, and trailer. Keep them inflated to their maximum, so as to reduce the amount of sidewalk flex and pressure gain. If you can fit a 225/75-15 on your trailer, it’s worth it to upgrade to a load range “E” tire that can run 80psi.

 

If you have any further questions, just let me know and I’ll try to answer them.

Edited November 11, 2018 by ducnut

[ASD Dad]

Sorry, but you are wrong.  A WD hitch sole purpose to is to DISTRIBUTE WEIGHT, hence the name.  When you load your rear axle up with the tongue of the trailer you are removing weight from the front of the tow vehicle.  The WD hitch's purpose is to transfer most of that weight back to the front axle.  If you have inadequate suspension and excessive sagging you need to weigh the whole setup.  The only time you should need airbags, helper springs, Timbrens or anything similar is if your factory suspension was never tuned for towing in the first place (like many 1/2 T trucks these days that are designed for comfort vs. actual usage).  Even then the only reason to use the helpers on the rear is to get the tow vehicle level, cosmetic (looks) or comfort.  You then need to tweak your WD setup once the bags are inflated or you added the new suspension helpers.  If you are not using the WD hitch to transfer weight you may as well just use a hitch ball.

 

If you tighten the chains on the Anderson or the bars on most any other hitch to the point you can "smoke the tires" you have set it up wrong and should not be driving it like that period let alone rain and snow.  Again, that is not the point of the hitch.  You can also have so little tension that if you have a heavy enough tongue weight you can lose all steering due to no weight on the front axle...  

 

I owned an Anderson for over a year.  My issue with it on my Tundra was two fold - 1) it was not made to transfer a lot of tongue weight and that is a well known issue on many forums.  I could crank those chains down until the bushings almost burst and I still could not get the amount of weight transfer I would like to see back to the front axle (This was done with multiple trips across a CAT scale).  2) the design puts a lot of stress on the coupler of the trailer.  The couplers of most trailers (the lift up latches) were never designed to have rearward pressure put on them and it is a lot of pressure.  There were premature failures of couplers in the past and some owners swapped out their coupler to a different design so they could keep the Anderson.  BTW - Anderson actually bought my hitch back from me after I proved I could not get the weight transfer needed with photos and videos of setting it up at the scales.  I bought it when it was first released.

 

The Anderson IS a very unique and light weight design.  It is dead quiet, clean and it removes porpoising better than others and is pretty simple to setup.  If you have the right combo of tow vehicle and trailer I still highly recommend them to many people.  As always it is up to the buyer to do their research.  Maybe they have tweaked the design since it was first released, I have not looked since I returned mine.

 

Maxxis and Kumho both make excellent ST tires.  Goodyear also has a new made in America ST tire that is getting excellent reviews.  I am not sure I would just inflate any of them to max pressure although that is the easiest.  You should follow the load chart from the tire manufacturer to get optimal pressure.  Weigh the trailer then figure out the best cold pressure off the chart.  If you over inflate you are going to get excessive wear on the center tread over time and make the trailer more "bouncy" on rough pavement.  Over inflating when towing is 1000x better than under inflating though so if you dont know your trailer weight then it is better to just max the tires.

[ducnut]

You’re never going to transfer weight onto the steer tires, as you’re trying to do, pulling a bumper pull trailer. It’s simply not possible, unless you “bridge” the weight, as I explained. Then, you’re unweighting the drives. That’s the whole purpose of a 5th wheel design, as one can set the kingpin forward of the drive axle and get weight on the steers. Your assertion that simply using a WD hitch on a bumper pull will transfer what you feel to be adequate weight onto the steers is never going to work. You’re trying to leverage weight through the whole length of the chassis by binding the hitch. All that does is create an enormous and excess amount of stress on the coupler. But, you go with it.

 

I agree. An Andersen does place load onto the trailer coupler. But, use airbags to support the weight and the hitch to stop porpoising (which actually does transfer some weight on the steers), then, you’re not placing undue stress on the coupler. My current setup has 40K miles on it, so quite a few miles compared to what most will have with their occasional use activities. I do grease the ball, because the ball/coupler interface does get dry and can squeak. But, that’s not the fault of the hitch. In my experience, I’ve not had any issues with the coupler.

 

I’ve had at least 1K pounds of tongue weight on this truck (extended cab with 6-1/2’ bed), using airbags. The most I’ve grossed is 22,500lbs, coming out of a quarry. The most I’ve had in the bed is 2200lbs. The frontend rises a bit, but, nothing objectionable. Even with 500lbs of tongue weight (about what I normally run), the frontend looks normal height. Keeping the rear at proper ride height, using airbags, is part of that. The further the rear suspension is mashed down, the more weight is transferred to the rear and the more the frontend will rise.

 

I’ve used this setup for work, every single day, during season; not the occasional recreational use. Your assertions are of ideal scenarios portrayed by marketers and that’s just not reality. All you can expect is the best you can do with what you have (hopefully the right equipment). Buy a semi-tractor and trailer, with adjustable fifth wheel and trailer tandems, if you seek perfect weight distribution (I have 27yrs experience in trucking). Even then, they don’t always pull perfect in every scenario.

[ASD Dad]

You are still wrong.  It is simple physics on how a WD hitch works and is the whole reason they are made in the first place.  Go ask Anderson - they will tell you that their hitch is designed to move weight off the rear axle and back onto the front axle.  Period.  Want more proof - go ask ANY manufacturer of WD hitches how and why they were built in the first place - Reese, Curt, Husky, Anderson, Blue  Ox, even big dogs like ProPride and Hensley.  They are ALL designed to transfer weight from the rear axle that was loaded with your trailer and move that weight back to the front axle.  All. Of. Them - even Anderson.  All your airbags are doing is reducing rear end sag.  

 

I hope with 1000 lbs of tongue weight and 22,000 lbs gross you are not in a 1/2T Silverado...

 

My assertion is from decades of towing, doing research and talking to the actual manufacturers of the hitches.  No, I am not commercial driver but I know plenty of them.  I also dont tow daily but I do tow thousands of miles a year and have 3 more 1000+ mile trips coming up very soon.

 

By your reasoning there is no reason to have a WD hitch at all.  Just put your trailer on a ball and add airbags...  Dont tell me it is to reduce porpoising.  

[ASD Dad]

I am 99.9% sure this will not change your mind but I dont care.  This is for everyone else to do their own research based off physics.  What you are suggesting to people is borderline dangerous in my opinion.

 

https://www.etrailer.com/faq-weightdistribution.aspx

 

http://rvlife.com/how-weight-distribution-hitches-work/

 

http://www.trucktrend.com/news/1602-five-things-you-need-to-know-about-a-weight-distributing-hitch/

 

https://auto.howstuffworks.com/auto-parts/towing/equipment/hitches/towing-weight-distribution-systems.htm

Edited November 12, 2018 by ASD Dad

[andy_george]

I understand that ASD Dad and ducnut won’t be meeting for a beer anytime soon, but good conversation like this informs everyone who reads it, and for that, I say thanks!

[radin2son]

I’m curious about ducnut and interest in NVs, towing and conversions posts. I can find 3 of 4 posts, but not the first which may address this. Driving a Silverado is not the same as driving a NV. Both trucks, yes, but way different, particularly the 3500.

 

Not another mental exercise, I hope... If ducnut intends to own/drive an NV, then this could be productive.

[ducnut]

Nowhere did I say there wouldn’t be ANY transfer of weight.

 

You act like using a WD hitch makes everything perfect. It doesn’t. A WD hitch creates a bridge between the steer axle and trailer axle(s). It doesn’t makeup for the fact the tow vehicle’s factory suspension isn’t capable of supporting the tongue weight, at a level ride height. When you use a WD hitch to correct that, by attempting to take weight off the drive axle, you unweight the drive axle of necessary weight needed for stability and puts an incredible amount of stress on the coupler/hitch, trailer chassis, and tow vehicle chassis. Ideally one would want all the axles carrying similar weights.

 

Manufacturers promote a WD hitch as a way to “tow level”. When one adds say 500lbs of hitch weight and the vehicle sags, the only way to get it back to level is to completely remove the weight from that suspension, so it can return to “normal” ride height. That 500lbs doesn’t magically disappear; it gets distributed elsewhere, through leverage on the tow vehicle’s chassis and trailer’s chassis, through tremendous forces at the coupler/hitch. What you end up with is a combination vehicle that is loaded at each end, but, not in the middle. During a panic maneuver or on a compromised surface, such as snow, ice, or wet pavement, you’re setting up the combination for a jackknife, because the ends have traction, but, the middle doesn’t. You want your tongue weight to be carried by the drive axle. The brilliance of the Andersen hitch is that the tongue weight driving the ball down in the taper creates anti-sway. The more tongue weight, the more effective it is. If one uses the airbags to support the weight, the Andersen takes care of the sway. That’s why I’m a firm believer in the product.

 

Years ago, I took a trip up to Lake Superior, with a friend, to go snowmobiling. We took his 3/4T Suburban and tri-axle snowmobile trailer. He hooked up the trailer, raised the tongue as far as possible to preload his WD hitch, hooked up the torsion bars, and lowered it all down. The combination was pretty level. We get up into inclement weather and the rear of the tow vehicle is skating around. We pull into a poorly plowed fuel station and we were stuck. He had to engage 4wd, to pull our way through. Why? Because he had the weight “bridged”. I can’t tell you how many combination vehicles with WD hitches I’ve seen jackknifed in poor weather, even rain. Heavily preloading the WD hitch to do as many claim one should, simply isn’t safe. Ideally, one would want all the axles to be carrying similar weights, so each tire has equal weight and traction potential.

 

The trucking industry has started pushing for drivers to run the trailer tandems as far forward as possible, to better shroud the trailer tires from airflow coming off the side skirts. Steer axles weights only vary 1000lbs, loaded or empty. The huge variations come at the drives and trailer tandems, depending on where the tandems are set. If we do what mgmt tells us and slide the tandems forward, that takes weight off the drives. Also, it puts more weight behind the tandems, which creates a pendulum effect. Have you heard the heard the expression “The tail wags the dog.”?. That’s exactly what happens. The towed axles are carrying more than the drive axles, which is a surefire way to a jackknife. If one looks at crash footage of European semi-trucks, the second thing that happens after applying the brakes is a jackknife. Why is that? Because they run a single-axle tractor with a 3-5 axle trailer. There’s very little total weight on the towing vehicle, compared to the towed vehicle. North American configurations are much safer, IMO. But, it illustrates why a combination vehicle needs balance. I always adjust the tandems to carry equal weight, so everything is balanced, regardless of what the industry is pushing for. Further, the stability and ABS systems are designed to operate with the load being balanced.

 

I’m not going to change your mind. I know that. You’re going to continue to throw in anyone’s face those links, as you did me. But, the fact remains, a heavily torsioned WD hitch unweights the drive axle, while loading the end axles, and creates weight imbalances that can contribute to a jackknife. That is why a 5th wheel setup is always recommended as the safest way to tow any kind of trailer; they carry nearly ALL the tongue weight on the drive axle. Now, I know that’s not always practical, but, it is the fact. Just as it is fact for a vehicle to be able to ride at an unladen level, with a trailer in tow and a WD hitch being used, the drive axle can only be seeing close to unladen weight to not sag. All I tried to do is bring a common-sense, real-world view to the topic, free of industry propaganda, using 27yrs of traveling the country, all my years of towing every kind of trailer imaginable, and approaching 3M miles of accident-free driving. You all can tow your stuff how you like. Peace.

[cgeggatt3]

Thanks guys lol andy_george you may be right!

[ASD Dad]

I never said you had to remove all the loaded weight placed on the rear axle using the WD hitch.  Go back and read my posts.  The fact that WD hitches are Required for many trailers on many vehicles by the tow vehicles manufacturer should be enough of an excuse to use one.  You get over a certain tongue weight - use the WD hitch period.

 

You do want to try and restore weight back to the front.  The reason Anderson would not work on my Tundra was it could not transfer enough weight back up front.  My front steering was way too light and it would actually trigger the ABS/traction control system on off/on ramps for highways due to the front slipping.  Not fun.  The Tundra suspension is tuned for comfort in daily driving, not hauling a load.  The rear end squat was ridiculous and the front unloaded hundreds of pounds with a modest tongue weight.  The Anderson design was simply not setup to transfer the amount of weight I needed to get my steering back.  I will agree it is a great design for the right setup.

 

You get a strong enough WD system and you can almost suspend the back axle of the tow vehicle.  I never once said to do that or to set it up that way.  I will agree 100% that is wrong and dangerous.  What your buddy did with his snowmachine setup was wrong.  I have been in plenty of slippery situations with my camper in tow (rain, sleet and sand) but no snow as we dont camp in the winter.  I have never once had a traction issue due to weight issues over the rear axle and I still have a good amount of squat on the rear of my NV even with a properly setup WD hitch.  I am removing a percentage of the weight and moving that weight off the tongue and back onto my steer axle and trailer axles.  Not all of it or anywhere close.

 

I am done.  I left links for people, anyone, to do their own research and they can contact their hitch company and/or tow vehicle company if they want further information.

[Simon & B]

From the 'small' end of the scale:

 

For what it's worth, we tow a 3,500# 'bumper pull' travel trailer with our NV3500 Cargo van. We don't really need a weight distribution hitch, as the tongue weight is around 450#. We tried towing it without our Andersen, and immediately put it back on, as it 'tightened up' the 'connection' between the NV and the trailer, and made for a much more pleasant driving experience.

 

Previously, when towing the same trailer with an Xterra, the Andersen hitch saved our bacon quite a few times with its 'anti-sway' features. It certainly made driving the equipment much more tolerable. I agree that its weight transfer is not very great at all, I think we measured it at about 100#, spread roughly equally between the front wheels of the tow vehicle and the trailer wheels. On that Xterra, we had air bags installed on the rear axle, but with the Andersen setup, we never found it necessary to use them, as the rear of the Xterra hardly 'sagged' at all, when the Andersen was set up as directed.

 

I don't think that removing 100# from the rear wheels of the tow vehicle is going to cause them to slip and slide in snow and rain, especially as you've just added 450# to them (in our case).