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Payload question

6K views 29 replies 10 participants last post by  luckyhat12 
#1 ·
I have a stock 2500, quad cab, short bed.
I found a great deal on a cab over camper, wife really wants it. The dry weight of camper is 1500 lbs. don’t really understand how to figure payload, so basically is this payload weigh ok? Would anyone think I would have to bag the truck? it won’t be on all the time just to use on occasion. I still have stock trans, will this weight kill the stock trans? Sorry if this is a dumb question. I just don’t want a fun project to turn into a big headache for me. Thanks in advance
 
#3 ·
A camper is not going to stress the transmission at all. And payload is the amount of weight the truck can carry. 1500 lbs is fine but you'll want E rated tires and some sturdy shocks to handle sway.
 
#5 ·
Katoom i right on. But. 2500's are not "rated " for cab over campers based more on center of gravity more than payload. But 1500 is light for a cabover. Is it designed for a short bed? Meaning the bottom is not over 8 ft and will end at the tailgate. Your load capacity is about 2200, that counts camper, passengers and cargo. Overall you will be fine from practical point of view. HD or adjustable shocks needed. Camper special package option build code AHJ,(overloads and sway bar) is best Airbags are fine if you want them, they may help. If your truck does not have it you can get it from the wrecking yard and bolt right on
 
#6 ·
The only issue is whether it’s a shortbox style camper or not. If it’s a longbox camper you don’t wanna go over 8’ floor length.

Camper “dry weights” are 100% BS. In the truck camper world (that I’ve been in for 30 years), you can generally add 800-1000 pounds to the so-called “dry weight” to come closer to what it’ll really weigh all set to go.
Literally no RV ever weighs the “dry weight” going down the road. Scale it, you’ll see.

The truck has the same chassis as the long bed, just shorter. They make lots of campers for them. Run E-rated tires.
You can use air bags or for a simple and cheap solution that’s very effective and popular among truck campers, look into “Timbren” overloads. Personally I like airbags with an onboard compressor because it’s so easily adjustable to however stiff I need.

If you don’t have a sway bar, you might want one. Helwig makes one that fits these trucks. I’ve got one on mine.

The advertised load capacity on pretty much all 3/4 ton trucks is artificially low. That number is usually pulled out of a hat for licensing reasons. Nothing to do with what the parts in the truck are capable of. Dana rates your rear axle a whole lot higher than Dodge does. Generally with a truck camper your real limit is your tire capacity. But you’re fine with any shortbed camper, unless it’s one of a couple newer triple-slide-out short box monsters they’re making nowadays. If yours has a 1500 pound “dry weight” it’s gonna be fine, even though it’s gonna weigh more than that.
 
#7 ·
Thank for reply’s. I am positive it’s 8’. It’s a 8’ Alaskan hard sided pop up cab over. I called Alaskan to get the 1500 lbs weight number. While my wife wants it for a project, it will mostly get used for a rolling bunk house when I hunt in Mexico. I’ll probably remove things like the fridge and stove. And make strictly a bunk house maybe room for cooler, dog, gun rack etc.
 
#30 ·
Based on everything I've read... Alaskan campers are a completely different animal than most of the other truck campers. There are exceptions that can be had with them that aren't like a lance or arctic fox or the bigfoots.... I hope it is everything you want it to be. They are made to be a bit lighter for overlanding to a point.
 
#8 ·
When I bought my truck new there was a "camper package" option.
My truck has this option.
I believe this is just extra leaf springs.
Here's a photo of the passenger's side:
 

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#10 ·
That would be the Camper Special. But... you'll still be needing some good shocks as campers will cause considerable side to side roll on a SRW truck.
 
#11 ·
No worries.
These trucks are over-loaded all the time. Your 1500 lbs will be 2500 lbs very quickly, but that still is nothing for the 2500 series truck.
You didnt say what year truck. Older one will have sagging leaf springs.
If you have a leveling kit then that is wrong. If the truck sits high in the rear unloaded then it should sit flat when loaded with TC. Not ideal to be sitting on the helper springs when loaded as you will have a harsh ride, but it will drive just fine. Your pic seems to be a long way from sitting on the helper springs so you should be fine without bags. If TC does not make it sit on helper springs, then you are fine.

Beware that if the rear sags too much the truck will handle poorly. Unweighting the front end (wheels and axle) will change the dynamics of handling and braking and steering. You need to keep truck relatively level. Add air bags if necessary. Put the bags on the leaf springs, removing the helpers if necessary. With a TC never put bags inside the frame (on the bump stops) as your truck will be wobbly. Put bags as far to outside as possible, which is on the springs, where the suspension already is to begin with.
I say airbags and not new leaf springs since you dont plan to be a full timer, so bags let you stiffen suspension when needed then go back to normal the rest of the time when no camper. I prefer bags for full timing personally…

Weight wont matter to trans, but the extra air resistance on highway will. Put in a trans temp gauge and keep temps down, and beware of overdrive (5th gear in manual). Don't plan on driving too much over 65mph.

Keep fridge in there. It is such a great thing. Keep fridge level when parked and fridge is running. You will not be saving any significant weight removing it and you will enjoy having it in there so much more.
I wouldnt remove anything. You have a camper, enjoy it. Maybe remove the roof AC if you have no way to power it up (big generator or outlet) as it is extra wind resistance and extra height and lot of weight on the top.
 
#12 ·
As far as weight transfer goes, there is none from lifting the rear back to level from sagging, that’s just an optical illusion.

I’ve parked my air-suspension truck on a scale and adjusted it up and down with the camper on, zero difference in axle weight.
I’ve also put the other end of a car on a tow truck on a truck scale and lifted the car up and down to see how much tilt it took to change the weight, it was a whole lot of tilt. Way more than the sag a pickup with a camper ever has.

This is just like back in the ‘60s when gasser-class drag cars ran nose-high for supposed weight transfer. It wasn’t real and it’s only ever done now for nostalgia reasons.
 
#14 ·
Are you trying to say that lifting the rear end a few inches takes weight off of it and sends it up forward?
Try it while sitting on a scale... like I have.
I’m not saying don’t beef up the rear suspension and level out the truck, but that’s so the headlights aren’t in everyone’s eyes, the rear isn’t too spongy, and it doesn’t look screwy. But that doesn’t change where the weight is.
You have to change the attitude of the truck at least 15 or 20 degrees before you see any measurable difference in actual axle weights, and even then it’s slight.
You have to get closer to 30 degrees before weight transfer starts getting significant.
A pickup that sags under a camper just isn’t tilting that much.

The better handling you notice is from stiffening the suspension up.

I’m not guessing, I’ve scaled this stuff. I run trucks for a living.
 
#15 ·
The camper is painted white usually to make them lighter.

It made no sense that you could think anyone was thinking that adjusting the suspension up or down changes the weight of the truck.

Youre right that angles will not change weight, I guess that was spoken wrong. Weight distribution is minimally affected. The angles mess with the steering geometry. The bags make the suspension adequate.
 
#16 ·
I guess I just learned something here. . .

I too was under the impression that if I lifted my truck's rear I could shift a 100 pounds or so to the front axle.

I have RideRite automatic airbags. I keep them at 35 PSI.
(I personally feel the airbags are unnecessary and just suck up valuable payload, but that's another topic)

>> Stock RAM 3500 with 3700 Lb Arrow-U camper.
Seems to 'not' squat even though it's (RV-typically) over GVWR. . .



>> I'd feel a lot better if I could (magically?) transfer 200 hundred pounds to the front axle since I'm at max rear GAWR (7000#).



Now I'll have to hit the CAT scale once with 15 PSI in the bags, and once with MAX PSI and look for any weight transfer to the front axle.

Interesting thread by @JBK2 and thanks @Monstermaker & @andytruck for your counter-views. :thumbsup:
-Ej-
 
#17 ·
I too was under the impression that if I lifted my truck's rear I could shift a 100 pounds or so to the front axle.

>> I'd feel a lot better if I could (magically?) transfer 200 hundred pounds to the front axle since I'm at max rear GAWR (7000#).

Now I'll have to hit the CAT scale once with 15 PSI in the bags, and once with MAX PSI and look for any weight transfer to the front axle.
-Ej-
I think you can shift some weight forward, Ej. The higher the center of gravity (and a heavy camper certainly qualifies) the more weight shift will occur for a given "tilt".

But if that same weight was all below the bed sides, the difference probably wouldn't be measurable without precision instruments.
 
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#18 ·
Someone said it along the way years ago probably and it made sense if you didnt think about it. Now that we are.. there is no shift in weight from adjusting the height.
The weight shift already came from the TC loaded into the bed, shifting more percentage of weight to the rear. Depending how rear-heavy the TC is maybe the rear axle acts like a fulcrum and does lift the front end, taking weight off the axles (which is really bad),but this is not the discussion.

You wont put weight back on the front by raising the rear a few inches, but that is not the purpose of the air bags (or other means of ride height correction). The purpose is to get the truck back to a level driving position.

Interesting thing happened to me.
I drove with the TC and had too much air in bags. I had mistakenly taken forum advice and aired the truck to be back to empty height, rear higher. For some reason the front tires were wearing on the edges, feathering, then having a noticeable vibration. I had driven maybe 1,000 miles to this point. I decided that the truck wanted to be level when loaded so lowered the bags. Trucks are rear high because they are meant to be loaded, and the load will put the truck at level.
When loaded something was happening on the front end (caster?) to wear tires that, at the same rear-high angle, did not happen unloaded.
That was my logic and it corrected the wear issues.
I suspect that the added weight sank the front springs a little and changed the angles of the frame to front axle (4x4 axle), thus steepening that caster (or something) and then raising the rear caused more steepening so compounded the effect.
Two facts I know are 1. truck was loaded and rear-high, and 2. tires wore in this position. Well, 3 facts, 3. tires did not wear in level position.
Go figure…
 
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#20 ·
I suspect that the added weight sank the front springs a little and changed the angles of the frame to front axle (4x4 axle), thus steepening that caster (or something) and then raising the rear caused more steepening so compounded the effect.
Adding weight up front could increase caster (depending on suspension design) by lowering it, but raising the rear would decrease it.
 
#19 ·
^^^ Very analytic. Gives me something to think about.

Next time I’m at a CAT scale I’m doing the “rear height” test.
And of course a lot depends on the repeatability of the CAT scale itself.

I have a short-bed camper rig and I love the added maneuverability, but man, center of gravity on this thing is unforgiving as hell.

Thanks for the input on this stuff! :thumbup:
-Ej-
 
#21 ·
^^^ Very analytic. Gives me something to think about.

Next time I’m at a CAT scale I’m doing the “rear height” test.
And of course a lot depends on the repeatability of the CAT scale itself.
-Ej-
Save your time. The scales will give the same weight at all heights.
Interesting would be to measure weight at each axle with and without TC to see the split.
 
#28 ·
I was given one to "give it a go" when they first came out. Stuck it in the receiver of a Jeep and went up one of the driveways, with a small hump in it.

Sure enough, once the Hitch Helper reached the top of the hump I had to put it in 4WD to keep going.
Also, even with it sitting only about two and a half feet behind the rear axle, predictably the tire scrub was horrendous when turning. Thankfully it was on dirt.

I'd think the concept could be made to work, but it'd require real tires and wheels and a swivel function. Wouldn't be too hard to build, though.
 
#29 ·
1.) Thanks for the clarification!
Call me naive on this stuff, but I'm just looking for a 'magic bullet' on these payload issues.

2.) I guess we pretty much killed the thread seeing as how we obliterated JBK2's original question. :rolleyes:

As I recall it was something about putting a truck-camper in the back of a (coil-sprung?) 2500 short-bed...
I'm maxed out with a "small" camper in my leaf-sprung 3500 so I'd imagine @JBK2 will have quite the task on his hands.

-Ej-
 
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