Chucking - trouble shooting

[dkuntz]

I’ve found a few strings in the forum on this topic. I’ve come to the point where I’ve concluded there isn’t a silver bullet to resolve the issue unless I want to spend several thousand on a TrailSaver hitch in the truck - which only eliminates the feel of the chucking, not necessarily the chucking. That being said, I’m looking for advice on where to start the process of elimination to first minimize the chucking coming from the trailer, and then the steps to minimize the impact at the truck.
1) Fill the trailer/truck so its loaded similar to how I will be camping and use that as a baseline for the chucking.
2) Add equalizers/shocks to the leaf springs on the trailer
3) Upgrade the factory king pin on the 5W to a MorRyde type rubber pin box
4) If that doesn’t eliminate 95% of the chucking on the truck, then I may have to look at getting an air system hitch on the truck.

For those that will ask; I have a 2019 2500 Duramax, pulling a 2020 5W Keystone Cougar 1/2 ton 29MBS. I’m within all charts/weights/etc. King Ping weight is 1,700lbs. Tire pressures are as spec’d (even though I don’t agree with the people on the forums that this matters with chucking). I added B&W gooseneck hitch to the truck frame and bought the Andersen Ultimate hitch in the truck bed along with the locking plate to the king pin box. The trailer has a front bedroom, middle bunk house, and kitchen in the rear. Cougar has stock “Road Armor” suspension system on the axles. I’ve only towed it so far completely empty from the dealer and to the storage facility. The chucking was miserable.

[eHoefler]

Check the location of you pin in relation to the center of axle. Chances are you are on center if not behind, common with short bed trucks, to get turning clearance. For proper loading and ride, center of pin needs to be 2"-4" ahead of center of axle. Moving your fifth wheel forward is a low cost improvement with great gains.

[southernsky]

Pulling a 5th wheel for over 10 yrs, bumper pulls before that. Three different trucks, three different 5th wheel trailers and not sure what "chucking" is. My rigs have pulled tight without bounce or noise. All three trucks were Ram 3500 duallies and I do run air bags on them. All three trailers have had some sort of equa flex suspension systems and air ride pin box. Guess I've been lucky or something to not have a the "chucking" problem

[rhagfo]

dkuntz wrote:

MFL wrote:
You're using the wrong number. With a FW all the pin wt goes on the rear axle. You have lots more available pin, likely 2500-2800 lbs, and still under axle rating. That payload is just the weight of your truck subtracted from a class 2 GVWR.

Jerry

I agree the truck can handle another 1,400lbs per the axle/tire ratings, but I’m not aware of any other “numbers to use” other than payload as its the most restrictive. Payload is what is calculated as any weight added to your truck, regardless of where on the truck its added. Being in Colorado with some serious grades and the fact that I’m double towing, I don’t play around with capacities....seen too many out of control trucks from people not respecting them.

Regular size 5W’s with the layout we wanted were too long for me to double tow, so I had to go to with the 1/2ton model to keep my overall length under 65’ for the State’s I’ll be towing through. Regardless, I’m asking about chucking improvement here as I already have the truck and trailer

If you are double towing you absolutely need more pin to compensate for the hitch weight on the back of the 5er. Just get a truck with enough capacity to handle the weight you are towing.

[lenr]

Our chucking was 50% solved with a MORryde pin box, first. Then 98% eliminated by installing MORryde SRE4000 rubberized equalizer. The 4000 does this by reducing the jarring to the trailer which is another benefit of it. Watch the video on the MORryde web site. Both are easy to install and reasonably priced online.

[JIMNLIN]

I’ve come to the point where I’ve concluded there isn’t a silver bullet to resolve the issue

Just part of your questions but your correct ....there is no one thing that works for all chucking issues with a truck and 5th wheel or GN trailer.
I've seen post where the OP had chucking issues. He tried adjusting air pressures on the combo.....new shocks on the combo....even new tires and other low cost fixes that others had done. Nothing helped.
He finally moved the hitch back two inches in front of the trucks rear axle. This cured all his chucking issues. The rv dealer had the pin in his long bed set up 4" in front of the axle.

I had bad chucking issues with 32' 5th wheel rv trailer. It came with a 30" extended pin box which had the overhead about 6" from the end of a long bed DRW. I went with a 12" extended hitch box set to the same height and no more chucking.

What works for you will be just that and may not work for others.

Any wayz ....you could be short changing the trucks load carrying ability and as one member pointed out the overloads maybe carrying just enough weight to have a short compression and a severe rebound.

Google has loads of fixes for those that had the issue. You might wanta' spend some time doing that type of search.

[Cummins12V98]

Air ALL tires based on load plus 5psi. Bilstein 4600 shocks. Trailer LEVEL. If u have air bags only add enough air to keep truck LEVEL. Monroe 555001 shocks on RV. 20% pin minimum, closer to 25% the better.

Be sure the ANDERSEN is PROPERLY fastened down!!!!!!!!!!!

[garyp4951]

I think you need to load it up, and then see if the added pin weight helped.
You can't go wrong with a MorRyde pinbox, and Dexter EZ flex set up, and I'm sure it will be an improvement over the Lippert Road armor.
If your getting too much squat, and running on the overloads, add air bags to cushion, and level the truck.

[azdryheat]

My chucking went away when I replaced my worn out/inadequate suspension components with EZ Flex. Used to be terrible chucking going over bridges and bumps. Sometimes I thought we'd loose the trailer it was so bad. With the EZ Flex that is all gone, well the majority of it. Cost me about $600 for three axles and the kit came with wet bolts so no more squeeks. Money well spent.

[dkuntz]

Got it, yeah that makes sense. I’ll have to check that. Thanks.

[mapguy]

dkuntz wrote:

I don’t know what this is or I’m not understanding what you’re referring to. Thanks.

Sorry - truck rear axle leaf springs from GM has an overload leaf configuration. AS it squats the overload leaf engages. They are setup this way to give a better empty ride.

[dkuntz]

mapguy wrote:


A third thing is concerning the factory overload engagement. IS it staying fully engaged or fully disengaged? If spring is bouncing off overloads -the ride suffers greatly

Good luck!

I don’t know what this is or I’m not understanding what you’re referring to. Thanks.

[mapguy]

Before doing an accessory buying -make sure your towing setup is correct.

Trailer frame needs to be level (parallel) to ground when hitched/loaded. Don't eye ball it -measure the main frame near rear and in front before the frame step up. Proper setup has these numbers nearly identical. My personal limit is one inch maximum difference with front being higher than rear. You ask why only an inch - because additional front height compromises suspension travel which amplifies the issue you are having now.

The next most important thing before investing in a cushioned pin box or hitch is Pin Weight. From my experience, which pretty much mirrors rhagfo above, is that as a percentage -Pin Weight needs to be around 20% of actual loaded trailer weight for the best ride.

A third thing is concerning the factory overload engagement. IS it staying fully engaged or fully disengaged? If spring is bouncing off overloads -the ride suffers greatly

I am a firm believer in having real shock absorbers on the trailer axles, too. They just calm the trailer down by getting rid of the sharp impacts.

Good luck!

Use Gross Axle Weight Rating when determining loads being acceptable or not. A trip to the scale is a very good idea -that way you know what the weights are exactly. You only tow "dry" one time on the trip home from buying the trailer.

[rhagfo]

dkuntz wrote:

Flute Man wrote:
Maybe your pin weight is too light.

Funny story - a 3/4ton duramax only has 2,150lb payload - so 1,700lb pin weigh is right where I want it before I add my family and other stuff to the truck.

Well sorry to say with a 2,150# payload, and already 1,700# dry pin that only leaves you 450# before you max payload, you always planing on hauling the 5er empty??
You have two choices, go by rear axle rating or get a bigger TV.
You state family, likely a couple kids and wife, maybe a dog, food. To stay within numbers not enough Truck.

you really need about 22% to 25% pin otherwise the 5er is trying to rock back and forth on the axles.

[ChuckV1]

I upgraded to a 18k MorRyde pin box an changed for a 16K 5th wheel to a B&W patriot 18k ... I will say that the MorRyde pin box solved 90 percent of the chucking an replacing the 5th wheel hitch took care of the rest ...

Safe Travels 🙂

[goducks10]

Knowing what I know now and having a truck with a gooseneck hitch in the bed I would've went with the Reese Goosebox pin box. I tried the MR pin box and while it will relieve some chucking it won't relieve all of it. Even MR says it won't relieve 100% of chucking.
Shocks and a MR3000 will help a little but won't cure. IMO nothing cures it 100%.
You either have it or your don't. Problem with looking for cures is everyone tows a different 5er with a different truck.
LOL, I always though the best way to buy a 5er and truck is to ask the question, "Who doesn't have chucking"?. Then look at what they own and go buy that.

If it were me I would sell the Andersen and get a gooseneck pin box with a bag. It's going to be as good as the MR and now you don't have to deal with the Andersen in the bed. Once you're unhitch you bed is clear.