Air bags vs weight distribution hitch

[phatboy64]

I need some help understanding this.

First my situation - I have a 26 foot inclosed V nose trailer. GVWR is 9990 lbs. Each axil (2) is 5200 lbs. I am pulling this with the truck in my sig. I am in the process of installing Carli long travel air bags.

When I view the video in the link below it would lead me to believe that having air bags is less relevant then having a WDH setup. At least from making it safer to drive. So now I am feeling like I wasted money installing airbags and should just have bought a WDH, or do I need both? 10k does not seem like a lot to pull assuming the weight is evenly spread out in the trailer.

I have pulled 30’ boats for years and other trailers without giving it a second thought. The big difference is I will be pulling this trailer up and down the east coast all summer, most other times have been shorter trips.
Watching this video has me confused…


My questions Is, If I were to load up the trailer to the full load would I need a WDH setup? Or will leveling with the air bags be good enough.

 

[oppizzippo]

I've towed 14k a lot with just timbren bumpstop replacements and have been very happy. I think you'll like the airbags ao you can level it out. Personally never tried a WDH, but I don't think you'll need it for 10k.

 

[phatboy64]

I've towed 14k a lot with just timbren bumpstop replacements and have been very happy. I think you'll like the airbags ao you can level it out. Personally never tried a WDH, but I don't think you'll need it for 10k.

Thanks! That is what I am thinking all a long then I saw that video and it threw me for a loop….

 

[MarkCO1]

Level is more important than a WDH. Some people swear by WDHs, but in most cases, I believe it is misplaced trust. Harder on the trailer.

But no, with a 1 ton towing 10K, I'd not even consider a WDH.

 

[wyvern]

As others have echoed I feel like bags are the primary way to put weight back on your front axle, therefore making your towing experience more stable.

 

[phatboy64]

I am glad to know I was thinking in the right direction. Like I mentioned, I have never given it any thought in the past. I feel better now…

 

[jsalbre]

As others have echoed I feel like bags are the primary way to put weight back on your front axle, therefore making your towing experience more stable.

Air bags do not and cannot put any weight back on the front axle. Unless you have bags that change the laws of physics some how. All bags do is make the rear end stiffer and higher. They can be used to level the truck out, and to make the rear end less soft. Thats it.

If you want to put weight back on the front axle you can only do that with a weight distribution hitch.

 

[MarkCO1]

Air bags do not and cannot put any weight back on the front axle. Unless you have bags that change the laws of physics some how. All bags do is make the rear end stiffer and higher. They can be used to level the truck out, and to make the rear end less soft. Thats it.

If you want to put weight back on the front axle you can only do that with a weight distribution hitch.

Well, the physics does not agree with you. Even watch the video, it's clear that leveling DOES transfer weight. Sure, a WDH does more, at a cost that is not always better, but if you are going to be tossing out "Physics" then at least admit it.

Technically, the video only shows "Statics", but still.

 

[jsalbre]

Well, the physics does not agree with you. Even watch the video, it's clear that leveling DOES transfer weight. Sure, a WDH does more, at a cost that is not always better, but if you are going to be tossing out "Physics" then at least admit it.

Technically, the video only shows "Statics", but still.

That’s not correct at all. The video shows that when they inflated the bags the rear axle weight went up and the front went down even more.

 

[Brutal_HO]

As others have echoed I feel like bags are the primary way to put weight back on your front axle, therefore making your towing experience more stable.

Bags will absolutely not put weight back on the steer axle on a bumper pull.

That said, OP does not need a WDH to trailer 10K with a 3500.

(I say that with no knowledge of the tow capability of the Carli setup. My comment is related to stock)

 

[AH64ID]

Bags and WDH do two very different things, and shouldn’t be used interchangeably. They can however be used in conjunction with each other for the best towing experience with a bumper pull.

The simplest breakdown is that airbags are used for payload that isn’t tongue weight, and a WDH is used for tongue weight.

Weight changes applied directly over the rear axle have no effect on front axle weight, airbags are directly over the rear axle so they will effect rear axle ride height without effecting weight distribution.

Because tongue weight and WDH effects are applied aft of the axle there is weight transfer from the front axle.

These trucks rarely need a WDH, but even at low trailer weights the driving experience is greatly improved with a WDH.

 

[Pasta4lnch]

fwiw I have a 3500 w a 10k-ish bumper pull trailer. I got the sumo springs (before I towed, so I dont have a comparison without them). I was going to go w a 2500 w air bags but all the research on airbags point to them being a pita to maintain. For me, going to the 3500 without airbags was literally $500 more than the 2500 w airbags. No-brainer imo. I dont regret it at all. I'd rather have the buffer...

I also use a WDH, though w the trailer on without the wdh there is zero squat. My wdh, Anderson, does a lot for sway control too.

 

[wyvern]

Hm, I’m a bit confused on this point of contention actually. Wouldn’t this only be true if your load were perfectly over the rear axle? I actually drew a free body diagram to help talk myself through this but I’m still not seeing how raising up the rear wouldn’t put more weight over the front unless that load were perfectly over the rear axle.

 

[jsalbre]

Hm, I’m a bit confused on this point of contention actually. Wouldn’t this only be true if your load were perfectly over the rear axle? I actually drew a free body diagram to help talk myself through this but I’m still not seeing how raising up the rear wouldn’t put more weight over the front unless that load were perfectly over the rear axle.

Because the load of a trailer is behind the rear axle and on a pivot point (the hitch), so by shifting it up you’re not shifting any more weight over the front. Even if it were weight carried solely by the truck in the bed, we’re talking about a height change of inches over 20’. That’s not going to be an appreciable weight shift.

 

[wyvern]

Right, I was only accounting for payload in my FBD so I was not actually modeling the third fulcrum. With a third, (the hitch) I do see that raising the height will actually increase the force over the rear axle.

However with just two fulcrums (axles), you’re saying theoretically the bags would distribute weight over the front, but you can’t actually raise the rear up enough to achieve this in practice?

 

[Units]

fwiw I have a 3500 w a 10k-ish bumper pull trailer. I got the sumo springs (before I towed, so I dont have a comparison without them). I was going to go w a 2500 w air bags but all the research on airbags point to them being a pita to maintain. For me, going to the 3500 without airbags was literally $500 more than the 2500 w airbags. No-brainer imo. I dont regret it at all. I'd rather have the buffer...

I also use a WDH, though w the trailer on without the wdh there is zero squat. My wdh, Anderson, does a lot for sway control too.

I have the Anderson as well, primarily for the sway control, it works great once you get the setting it up part down pat.

 

[phatboy64]

I took a look at them today. They seem nice and at a fair price but I don't know enough to tell the difference. I really wanted to avoid dealing with a WDH but I am going to be doing a lot of highway driving all summer and if it is going to make the driving more "pleasurable" ... IDK.

 

[AH64ID]

I have the Anderson as well, primarily for the sway control, it works great once you get the setting it up part down pat.

Sway control is a gimmick, the best way to combat sway is to properly load your trailer. If you need sway control something is wrong with the trailer or the trailer loading.

As far as Anderson WDH effectiveness they aren’t know for being great. There just isn’t an effective way to transfer weight vertically by compressing a chain horizontally.

Hm, I’m a bit confused on this point of contention actually. Wouldn’t this only be true if your load were perfectly over the rear axle? I actually drew a free body diagram to help talk myself through this but I’m still not seeing how raising up the rear wouldn’t put more weight over the front unless that load were perfectly over the rear axle.

You would have to raise the rear a long ways to get the angle and gravity to transfer weight to the front axle.

It’s not the height change in the rear that makes a WDH transfer weight, it’s the lifting force aft of the axle.

Think about a wheelbarrow and lifting of the handles. It’s easy to lift the stand off the ground with the handles because of their location to the tire. If you lift at the stand it’s a lot higher lifting force to get the same weight transfer.