Chucking or bouncing?

[BirchyBoy]

I’m not sure what I’ve got going on but it’s not fun. I was posting about it in another thread but thought a new one would be better. For reference, here’s my setup:

2018 SD F-350 CCSB, gas, 3,860lbs payload
New Bilstein 5100’s all around
Reese puck adapter, Curt Q20 slider
New 34’ fifth wheel, scale weight 13k
Front axle 4,200, rear axle 6,000
Scale pin weight 3k with me, two dogs and a full tank of fuel
All weights are within the limits of the truck
The rear is sitting on the overloads

I added 20 gallons of water to see if it smoothed the ride, no change. Today I raised the pin box; t was 2.5” high in the front. It is now 1/2” high on the front. A little better but not spectacular.

I’m not sure if the rear of the truck is bouncing up and down or if the trailer is pushing/pulling front to back. My wife says it feels like it is front to back movement. It is smoother riding on pavement than on concrete slab roads.

I’ve got a budget of $1k to troubleshoot this further. Here are the options I see:

1. Airbags - only good if the rear is bouncing off the overloads
2. Moryde pin box with the front to rear and side to side movement
3. PullRite/Andersen hitch

Thoughts? Alternatively, if there is anyone in the Denver area with a lot of experience, I’d appreciate some help.

[goingwest]

4200 lbs on the front axle seems awfully light is there a way to get some more weight up there?

[Theunz]

First, off any manual slider is going to have a little play in the slide mechanism. Second, the distance from your truck rear axle to your trailer axles can cause some fore and aft motion on certain roads. There is variances from one section of a road to other sections so it may ride fine on some and not others. Some concrete roads have a noticeable (at least if you are standing there looking at it and not driving 60 mph) step up or step down at each expansion joint. Your pin weight seems fine and your front axle weight may not be much off unladen weight for a gas engine. My current trailer is my first with a MorRyde pin box and I feel that it rides better than any non cushioned pin box I have had. When I changed trucks with my current trailer I went from a Reese manual slider to the Andersen Ultimate hitch. I do feel that the hitch made a slight difference and is certainly much quieter. If I had to choose one of your options it would be to get a better pin box be it a MorRyde or one of the air suspended boxes. Full disclosure… I drove mostly lightly loaded semi’s pulled with a heavy duty class tractor for 40 years and all my 5th wheel combinations have seemed like a Cadillac in comparison!

[Old-Biscuit]

Originally Posted by goingwest

4200 lbs on the front axle seems awfully light is there a way to get some more weight up there?

OP has GAS engine so front axle is going to be lighter then Diesel
4200# sounds right

5th wheel pin weight carried by Rear Axle...hardly any weight transferred to Front axle


Chucking......
light pin weight, nose high, rigid pin box/hitch set up

[Old-Biscuit]

Originally Posted by goingwest

4200 lbs on the front axle seems awfully light is there a way to get some more weight up there?

OP has GAS engine so front axle is going to be lighter then Diesel
4200# sounds right

5th wheel pin weight carried by Rear Axle...hardly any weight transferred to Front axle

------------------------------------------------------------------------------
Chucking......
light pin weight, nose high, rigid pin box/hitch set up, short bed/wheel base etc

Think different pin box will be best option....smooth out the action

[BirchyBoy]

Thanks everyone. I’ll look at a pin box now and maybe a an Andersen/PullRite in a few months.

[kdauto]

Describe your chucking/bouncing issue better please. Has this trailer been hauled by another truck before with better results? This is a new or almost new trailer? Do you have experience hauling 5th wheels?

I fixed a nagging chucking issue on mine, but I had wear issues. I did upgrade the equalizer which made a major difference.

[Skilletface]

Originally Posted by BirchyBoy

I’m not sure what I’ve got going on but it’s not fun. I was posting about it in another thread but thought a new one would be better. For reference, here’s my setup:

2018 SD F-350 CCSB, gas, 3,860lbs payload
New Bilstein 5100’s all around
Reese puck adapter, Curt Q20 slider
New 34’ fifth wheel, scale weight 13k
Front axle 4,200, rear axle 6,000
Scale pin weight 3k with me, two dogs and a full tank of fuel
All weights are within the limits of the truck
The rear is sitting on the overloads

I added 20 gallons of water to see if it smoothed the ride, no change. Today I raised the pin box; t was 2.5” high in the front. It is now 1/2” high on the front. A little better but not spectacular.

I’m not sure if the rear of the truck is bouncing up and down or if the trailer is pushing/pulling front to back. My wife says it feels like it is front to back movement. It is smoother riding on pavement than on concrete slab roads.

I’ve got a budget of $1k to troubleshoot this further. Here are the options I see:

1. Airbags - only good if the rear is bouncing off the overloads
2. Moryde pin box with the front to rear and side to side movement
3. PullRite/Andersen hitch

Thoughts? Alternatively, if there is anyone in the Denver area with a lot of experience, I’d appreciate some help.

I too experienced a similar condition. I would recommend trying a few low cost items before reconfiguring what you currently have as it appears you have done some homework with your weights.

Provided there is room for adjustment, purchase a Stall Mat from Tractor Supply or any feed store, this acts like a dampener, make cardboard template for the holes, cut it down to where it is slightly larger than your Reese Puck Adapter, place it between the bed of the truck and the Reese Puck Adapter and fasten everything back down.

Replace that factory equalizer with a rubber cushion based equalizer like a MORRyde 3 or 4 thousand or a Road Armor.

At least on my set up those two things took out 80 percent of the chucking I had going on.

[Rhagfo]

Look at putting shocks on the 5er. I did this on our 5er and it helped a lot.

[traveldawg]

Here is my set up...

• MorRyde Pin Box
• Demco Hitchiker Autoslider (with no play)
• AirRyde Airbags
• Rancho RS9000's all around set on firmest setting
• SRE 4000 and Sumo Springs on 5th wheel
• Pin weight 2740
• 5th wheel axel = 11,340

All the 5th wheel weights seem a bit light to me, but it is what it is.

We've been about 7,00 to 8,000 miles towing this sumer. And we've been towing this for 4 years just as much each year (except 2020).

I can vary the air in the bags and have decided.....

• With no air the trailer bounces less but the truck rides a bit harder;
• the more I air up the bags, the more the trailer seems to bounce but the smoother the ride in the truck;
• beautiful ride on smooth roads no matter the air setting;
• bumps are handled very nicely with almost no transfer to the truck cab or bounding;
• roads with humps, frost heaves, dips, and such are AWFUL no matter what setting and require a slower speed;

My conclusions after all this are:

• I've got an appointment for a MorRyde IS installation/swap;
• I want to to try a hitch with an air bag in it;
• There are no good roads anymore; not interstates, not US highways, not secondary roads. There are roads with good sections but there are no good roads anymore. Even new roads, especially those with concrete sections, aren't even good.
  Because of the IS appointment I am done messing with my set up.

[CecilD]

Because of the high hitch design, fifth wheels push forward (chucking) when going over bumps while at the same time providing timed up an down motions (bouncing). If your wife's head is bouncing off the headrest, you are suffering a high amount of chucking forces (fore and aft) generated by the trailer. Because of their design, each trailer is different, and you won't know until until you tow with it. Mine chucked terribly.

Air bags to stiffen up the trucks rear suspension will help. As the trailer pushes down, it also pushes forward. Stiffening the rear suspension will reduce the downward push and at the same time reduce chucking forces. The trailer is still generating those forces so they end up being dissipated by frame flex and attacking the welds in your trailer. Plus, all the magnified bouncing forces generated by your truck will be transmitted to the trailer. Not good.

Upgraded shocks on the truck won't help at all with chucking. They aren't even in the chucking energy path.

The suggestion to put shocks on your trailer is a good one, as it reduces the tendency of the trailer to rotate around an east-west axis when going over bumps.

Putting on MorRyde IS may make chucking worse as you will lose all your axle equalization. Like I said, my trailer has independent suspension on all four axles (Torflex), and it chucks terribly.

My solution was a Trailer Saver TS3 air hitch. Because of its high hinge design, the hitch head retracts when it is being compressed, mitigating both chucking and bouncing forces. The trailer is still generating those forces, but the hitch is converting that energy into heat and radiating it into the atmosphere. A really comfortable tow is the result as the trailer floats behind the truck. Not going to buy one for a thousand bucks though, however, it will be a lot less than the IS suspension.

All this being said, no hitch (even a TS3) or suspension upgrades will mitigate, dips, sunken grades, railroad crossings, big holes, and frost heaves. The trailer is creating too much energy for that. Better to slow down if you can.

[corn18]

I have installed pretty much everything:

1. Andersen Ultimate w/ rubber bed mat
2. Air bags with on board compressor and remote
3. Rancho 4600 shocks on truck
4. Flex Air pin box
5. Road Armor Equalizer
6. MorRyde shocks on trailer
7. 3" lift (subframe add) on trailer to get it level
8. Maybe some other stuff I forgot I did

The one mod I liked the most for improving the ride in the truck while towing was shocks on the trailer. Not sure why that is, but that is my qualitative assessment. I'm not even sure any of the other stuff helped, but I spent a lot of money on it. I do think the FlexAir pin box helped, but not $1500 worth of help.

[freestyle_freddy]

Take a look at an Air Ride hitch. I have one & it helps a lot. Nothing will eliminate 100% of the chucking & porpoising, but the air bag/shock absorber combo helps smooth it out a lot. If you're limited to $1k budget, look on Facebook Marketplace for a used one. It might take awhile, but I'd bet one would show up eventually. I found mine, used, at my rv manufacturer's service location, for $150, when we stopped there for some service. Someone had swapped it for a Hensley air ride hitch & it had been sitting on an outdoor rack for 5 years. I cleaned it up & it works perfectly.

[PulNSerenity]

Originally Posted by corn18

I have installed pretty much everything:

1. Andersen Ultimate w/ rubber bed mat
2. Air bags with on board compressor and remote
3. Rancho 4600 shocks on truck
4. Flex Air pin box
5. Road Armor Equalizer
6. MorRyde shocks on trailer
7. 3" lift (subframe add) on trailer to get it level
8. Maybe some other stuff I forgot I did

The one mod I liked the most for improving the ride in the truck while towing was shocks on the trailer. Not sure why that is, but that is my qualitative assessment. I'm not even sure any of the other stuff helped, but I spent a lot of money on it. I do think the FlexAir pin box helped, but not $1500 worth of help.

I 100% agree with your FlexAir statement. It helped some, but the thing is WAY over priced for what it is & does! If it was $600-750 I would say it was worth it, but not the 12-$1,500 they charge!