I have a 2016 3/4 ton GMC gasser with Anderson hitch connected to a 32' trailer that weighs 12.5k with about 2100lbs pin weight. When traveling I get a jerking in TV when there is a load. Happens going up a hill or slight elevation in road. Usually felt more above 30mph. I have a cushioned pin box and Morryde Cre3000 added to suspension. Is this "chunking" or do I have an issue with slipping tranny or chugging motor. Can't see tach moving. Never happens on down hills or full throttle pulls up hills. No issues noted when not towing. It can even happen on smooth roads. Its not constant but happens enough to be annoying.

Actually it is called chucking and is caused by the push-pull effect of the truck and trailer on uneven road surfaces. Mine has some chucking on some concrete roadways even though they appear smooth. And none on others. And almost never on asphalt. Since you already have a Moryde pin box I don’t have any other suggestions.

I too tow with the Andersen and MorRyde, and it's a pretty smooth ride, some road conditions will create some chucking. Having the ability to adjust my aftermarket air bags , there has been on occasion where I could adjust the air pressure and it smoothed it up. But that has been rare . Generally it’s just the expansion joints .Hopefully you will get it figured out , your description of it sounds somewhat unusual .

You gave values of 12.5k# and 2,100# pin. Are those the dry weights from the manufacturers brochure, or did you actually weight your rig.Assuming those are your weights while towing, you are very light on pin weight. And I think the fact that it is a problem while angled up a hill, supports my theory.Experiment with increasing your pin weight and see if that helps.Your numbers are a 17% pin weight. Your goal should be more like 25%. Or at worst 20%.

bpounds, yes those weights are guesstimates. I have not weighted it but it did seem to ride better when I had a 3/4 full water tank. So you may be on to something. How to load up more pin weight? Got a full basement and fully loaded under bed...hmmm. I may have a way to weigh pin at home with a scale that I had from TT. Pin weight dry is 1660lbs and my guess was a little high on trailer weight. GVWR is 12K so I am under that probably closer to low 11K which still puts me at about 20%

I agree with bpounds; seems a bit light on the pin, so please weigh, or re-weigh, your rig, ready to camp. Also, how level are you? If you're more than a couple inches off-level (usually nose-high), you can experience chucking. Does this happen on all roads or just the ones you travel most frequently? Your length can have an effect in that you can develop a sort-of harmonic due to the distance between your truck and the FW axles. Speed can affect this, too, so speeding up/slowing down by even 1-2 mph, can change this.Lyle

Please help me identify 5th wheel towing issue.

laknox
Nomad
Aug 06, 2019
I agree with bpounds; seems a bit light on the pin, so please weigh, or re-weigh, your rig, ready to camp. Also, how level are you? If you're more than a couple inches off-level (usually nose-high), you can experience chucking. Does this happen on all roads or just the ones you travel most frequently? Your length can have an effect in that you can develop a sort-of harmonic due to the distance between your truck and the FW axles. Speed can affect this, too, so speeding up/slowing down by even 1-2 mph, can change this.

Lyle
ZeeLet50
Explorer
Aug 06, 2019
bpounds, yes those weights are guesstimates. I have not weighted it but it did seem to ride better when I had a 3/4 full water tank. So you may be on to something. How to load up more pin weight? Got a full basement and fully loaded under bed...hmmm. I may have a way to weigh pin at home with a scale that I had from TT. Pin weight dry is 1660lbs and my guess was a little high on trailer weight. GVWR is 12K so I am under that probably closer to low 11K which still puts me at about 20%
bpounds
Nomad
Aug 06, 2019
You gave values of 12.5k# and 2,100# pin. Are those the dry weights from the manufacturers brochure, or did you actually weight your rig.

Assuming those are your weights while towing, you are very light on pin weight. And I think the fact that it is a problem while angled up a hill, supports my theory.

Experiment with increasing your pin weight and see if that helps.

Your numbers are a 17% pin weight. Your goal should be more like 25%. Or at worst 20%.
cummins2014
Explorer
Aug 06, 2019
I too tow with the Andersen and MorRyde, and it's a pretty smooth ride, some road conditions will create some chucking. Having the ability to adjust my aftermarket air bags , there has been on occasion where I could adjust the air pressure and it smoothed it up. But that has been rare . Generally it’s just the expansion joints .

Hopefully you will get it figured out , your description of it sounds somewhat unusual .
BB_TX
Nomad
Aug 06, 2019
Actually it is called chucking and is caused by the push-pull effect of the truck and trailer on uneven road surfaces. Mine has some chucking on some concrete roadways even though they appear smooth. And none on others. And almost never on asphalt. Since you already have a Moryde pin box I don’t have any other suggestions.

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Please help me identify 5th wheel towing issue.

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