Frame Strength, Who to Believe! The RV Sales Guy or the New Truck Dealer? Maybe Neither?

[UHAULER]

⬆ From above article…

“(The trucks owners says) I knew the payload capacity on the truck was about 7,800 pounds and the camper dry weight was close to 5,000 pounds, but fully loaded, probably about 6,500 pounds."

If you Google the max payload capacity for a 2020 Ram 3500, you'll see a figure close to what Pavel quoted there: 7,680 pounds. However, that's only the case for a regular-cab, long-bed model with two-wheel drive and the 6.4-liter Hemi V8. The truck in question here is a crew-cab, short-bed with four-wheel drive and the 6.7-liter Cummins diesel, meaning its payload capacity is significantly lower. It's impossible to know the exact rating of Pavel's truck without having all the details regarding the trim and options, but Ram's spec sheet shows the payload capacity for a similar dually as maxing out at 4,190 pounds.” ???

It's very easy to know the truck's rating, take it and get it weighed, then subtract that from the gvw.
Maybe people should weigh their trucks before they buy them if they think they are going to be close on payload. Go on a test drive, pay 20 bucks at a scale.I'm sure the dealer would compensate you on an $80,000 purchase.

 

[CFMGarage]

This really just seems like costly ignorance. He also has a front bull bar subtracting from his payload.

If you look up some pictures, this is the same way that these RAM frames buckle when in a collision from the rear while towing. This truck is crazy overloaded.

Looks like an older guy too, he should have known better.

 

[AbleGuy]

Back when we decided to put a 10’ camper on our older K2500, we loaded it up and just went to the local dump and drove up on the cat scale there. Easy Peasy.

For peace of mind, you can easily weigh your rigs too.
Just go here for some help:

https://catscale.com/cat-scale-locator/

 

[rruff]

Seems like the larger issue to me is how the load is distributed.

He has a small motorcycle hanging off the back, but it looks like the CG should be close to the axle, fore-aft... 6" maybe? Not as terrible as some anyway. And though he is well over GVWR (~2400 lbs), I don't think the weight of his engine and cab caused this. The high stress failure point is right where you see it bent... which I've heard is an intentional weak spot on pickups for rear-end crash specs. At any rate, it's where the frame dips down. The frame is probably the same on all 3500 pickups...yes? Fully boxed? Though torsionally stiff frames are nice for camper hauling, they are inherently weaker for vertical loads... and they can be bent more easily when getting crossed up, too.

He was driving in Baja. Don't know how much offroading that entailed. Maybe... hit a bump too fast, had an "oh ********!" moment, then he was thankful that everything looked ok? You wouldn't have to get too crazy with a rig like that before something would break... even though it looks like it finally fell apart while cruising down the highway.

 

[vintageracer]

Monkey Humpin a Football Pic!

 

[JaSAn]

He has a small motorcycle hanging off the back, but it looks like the CG should be close to the axle, fore-aft... 6" maybe? . . . And though he is well over GVWR (~2400 lbs) . . .

No way to tell CG just by looking at a picture. Depends on where the weight is in relation to the fulcrum (rear axle). And distance from the rear axle is a force multiplier (lever arm).

One needs at least two weights of each axle independently:

1. truck without camper, full fuel tank, passengers.
2. truck with camper, fully loaded, full fuel tank, passengers.

Second weight will tell if you are over GVWR and/or GAWR.
If front axle weight is less with camper loaded you have too much weight behind rear axle.

 

[rruff]

No way to tell CG just by looking at a picture. Depends on where the weight is in relation to the fulcrum (rear axle). And distance from the rear axle is a force multiplier (lever arm).

Exactly... but the shell CG doesn't appear to be behind the axle, and the doorway/entrance is in the very rear. If they put heavy stuff (like water tanks, batteries, etc) behind the rear axle then they are doing it wrong. This is the camper here: https://www.eaglecapcampers.com/eagle-cap-1200 https://www.truckcampermagazine.com/buyers-guide/hard-side/eagle-cap-camper/ COG is listed as 59" which would put it right at the axle, but I don't know if that is empty or wet. Then there is the motorcycle off the back and what that contributes. I guess if you hit a big bump, on the way back up there is quite an upward force concentrated right where the front tie-down is located; it's the only thing keeping the camper from flipping over backward. I only see these things bent upward, not the other way.

Oh the luxury! I never looked at one of these ginormous truck campers before. 3 slide outs!

 

[DaveNay]

...then they are doing it wrong.

I think that summarizes the situation appropriately.

 

[Christian P.]

Perhaps some common sense here would have gone a long way. Look at the size of this thing!!!!

How can anyone on earth imagine this to be okay is beyond me.

 

[BritKLR]

Back in the day when I was really into TC's the big issues with these big heavy campers was something called "porpoising" where the leading edge of camper would start moving up and down to the rhythm of the road, wind, etc.....and it could be seen and felt throughout the entire truck. There was different shocks/stabilizers (you can see them just in front of the windshield on my truck) that could be added to reduce the porpoising but it always made me wonder the effect it had on the frame of the truck?
I suspect that was an additional issue resulting on this failure.

 

[ripperj]

As far as Ram is concerned the yellow payload sticker doesn’t even matter. Rams come with a 8 1/2x11” piece of paper that shows the slide-in camper payload, it’s hundred’s (many hundred) less than the listed payload. My 21 Ram crewcab longbed has a yellow sticker of 4259, but the silly paper has 3299.
Makes no sense to me that the info is not on a proper sticker, and not on an easily lost piece of paper


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[ITTOG]

Back in the day when I was really into TC's the big issues with these big heavy campers was something called "porpoising" where the leading edge of camper would start moving up and down to the rhythm of the road, wind, etc.....and it could be seen and felt throughout the entire truck. There was different shocks/stabilizers (you can see them just in front of the windshield on my truck) that could be added to reduce the porpoising but it always made me wonder the effect it had on the frame of the truck?
I suspect that was an additional issue resulting on this failure.

View attachment 758637View attachment 758638

Wouldd the entire camper porpoise or just the cabover?

 

[BritKLR]

Wouldd the entire camper porpoise or just the cabover?

It appeared to be the front of the cabover. It didn't happen all the time but, with the right combination of wind and/or road harmonics you could see it going up and down. Tightening the turnbuckles didn't seem to change anything since they were frame mounted and you have to be careful of over tightening them to the point of damaging the camper.

 

[rruff]

As far as Ram is concerned the yellow payload sticker doesn’t even matter. Rams come with a 8 1/2x11” piece of paper that shows the slide-in camper payload, it’s hundred’s (many hundred) less than the listed payload. My 21 Ram crewcab longbed has a yellow sticker of 4259, but the silly paper has 3299.

Good info! It's sensible to have caveats regarding load distribution, and height of the load.

 

[Buddha.]

What’s the correct truck for this camper?