Buckling bronco!

Tandem axle trailers the same size of a single axle trailer will be a much smoother ride when the numbers are dialed in. Made a living pulling both (enclosed trailers). Never again.

Without knowing any of your tow vehicles GAWRs and GVWR/vehicle type and not showing any actual scaled axle loads from the tow vehicle and trailer axle loads.... all we can do is guess.
Guessing leads to speculations and far out there opinions that won't help you with your issues.

Get some scaled weight numbers/measurements before and after. Then work with those numbers.

JIMNLIN wrote:
Tandem axle trailers the same size of a single axle trailer will be a much smoother ride when the numbers are dialed in. Made a living pulling both (enclosed trailers). Never again...

Actually that's my expectations too, that's why I'm surprised and this post.

In fact, tandem axle is easier to set up and it's almost naturally (or defaults) to being bubble-in-the-middle level on a relatively flat campsite and roads.

Sam,
The level of the TT has very little to do with how much the trailer will porpoise or with how well the WD works. Although you want to tow with the trailer in a level attitude for clearance issues and sway issues, the bouncing you are describing is probably due to an improperly set up WD hitch.

Take a long look at this thread for some direction in setting one up. Also the advice to get your rig weighed is right on. Without scale numbers everything is just a guess.
Barney

BarneyS wrote:
Sam,
The level of the TT has very little to do with how much the trailer will porpoise or with how well the WD works. Although you want to tow with the trailer in a level attitude for clearance issues and sway issues, the bouncing you are describing is probably due to an improperly set up WD hitch.

Take a long look at this thread for some direction in setting one up. Also the advice to get your rig weighed is right on. Without scale numbers everything is just a guess.
Barney

Scale numbers? I agree his setup is most likely the culprit but I have yet to see a manufacturer of a WDH tell you to go to scales to set one up. I also have yet to see an RV dealer take a rig to a CAT scale to set one up. It's done by measurements from a level surface, it's not a guess.

Forget it.

BarneyS wrote:
Sam,
The level of the TT has very little to do with how much the trailer will porpoise or with how well the WD works. Although you want to tow with the trailer in a level attitude for clearance issues and sway issues, the bouncing you are describing is probably due to an improperly set up WD hitch.

Take a long look at this thread for some direction in setting one up. Also the advice to get your rig weighed is right on. Without scale numbers everything is just a guess.
Barney

Wow, this is a rich material for information. I'm learning a lot already,

Thanks!

WVcampground wrote:
Snip...

Scale numbers? I agree his setup is most likely the culprit but I have yet to see a manufacturer of a WDH tell you to go to scales to set one up. I also have yet to see an RV dealer take a rig to a CAT scale to set one up. It's done by measurements from a level surface, it's not a guess.

There are several things wrong with this statement.
First, the manufacturer has no idea what kind of trailer or truck his equipment is going to be used on and so gives generic information on how to set one up. This is designed to get you into the ball park and may often be ok for some users but not all.

Second, The dealer is not going to spend the time necessary to properly set up the hitch because it takes too much time and time is money. Rarely do the generic setups get the WD exactly right for an optimal towing experience.

Third, most dealers techs just go by the book and set the hitch up according to the directions or just "how they always do it". This, in most cases, is not the best set up for that particular combination of truck and trailer.

Forth, The dealer cannot know exactly how the owner is going to load the trailer so cannot get the WD set properly. The only way to do that is scale the trailer.

Which brings us to to the last part of your statement which is not accurate.
Setting up the WD by using fender measurements is only a guess as to what is the best WD possible. Variations in spring movement and truck measurements make this method good for a "ball park" setting but to get it correct the only way is to measure the axle weights on a scale.

This is very easy to do now that scales are all over the place in truck stops, waste disposal yards, landscaping yards, etc. I used to weigh every year on my way South for the winter to make sure I was within my trucks ratings and to check how well my WD was holding up. That can change with wearing of hitch parts in certain hitches

Bottom line is that I would not trust the dealer to get the WD setup correct and would suggest to anyone that they should get scale weights if they are serious in setting up their trailer and truck to tow as well as it possibly can.
Barney

BarneyS wrote:

WVcampground wrote:
Snip...

Scale numbers? I agree his setup is most likely the culprit but I have yet to see a manufacturer of a WDH tell you to go to scales to set one up. I also have yet to see an RV dealer take a rig to a CAT scale to set one up. It's done by measurements from a level surface, it's not a guess.

There are several things wrong with this statement.
First, the manufacturer has no idea what kind of trailer or truck his equipment is going to be used on and so gives generic information on how to set one up. This is designed to get you into the ball park and may often be ok for some users but not all.

Second, The dealer is not going to spend the time necessary to properly set up the hitch because it takes too much time and time is money. Rarely do the generic setups get the WD exactly right for an optimal towing experience.

Third, most dealers techs just go by the book and set the hitch up according to the directions or just "how they always do it". This, in most cases, is not the best set up for that particular combination of truck and trailer.

Forth, The dealer cannot know exactly how the owner is going to load the trailer so cannot get the WD set properly. The only way to do that is scale the trailer.

Which brings us to to the last part of your statement which is not accurate.
Setting up the WD by using fender measurements is only a guess as to what is the best WD possible. Variations in spring movement and truck measurements make this method good for a "ball park" setting but to get it correct the only way is to measure the axle weights on a scale.

This is very easy to do now that scales are all over the place in truck stops, waste disposal yards, landscaping yards, etc. I used to weigh every year on my way South for the winter to make sure I was within my trucks ratings and to check how well my WD was holding up. That can change with wearing of hitch parts in certain hitches

Bottom line is that I would not trust the dealer to get the WD setup correct and would suggest to anyone that they should get scale weights if they are serious in setting up their trailer and truck to tow as well as it possibly can.
Barney

You're making some assumptions.

You assume that all RV dealers do not know how to set up a WDH. You're assuming WDH manufacturers put instructions in with the product to just "get close". They could easily put in those instruction "visit a scale, weigh everything, and adjust following this procedure".

You can go to a scale and adjust to your hearts content but then you need to load the RV and tow vehicle exactly the same every time you hit the road. If you're going to go to those extremes to get 100% dead on perfect, you need to have the weights 100% the same to maintain it at all times. Better add ballast as you burn off fuel somehow too.

It's not really worrisome. The lip of my cup just missed my mouth in my drive yesterday.

And it's sort of defy my expectations and conventional wisdom.

That with tandem axle and heavier TT, I thought it will be more stable. Yeah, it is for now swaying but the little buckling surprised me. And I won't believe that California and Nevada have the same contractor making that bad roads, lol.

Without knowing the tongue weight is 12% or so, setting up WD is just guessing.
I assume you mean bucking (buckling would be really bad), also known as porpoising. If you are traveling the same roads as you did with the previous trailer and this wasn’t happening, then there is most likely a tongue weight and/or WD setup issue.