1972 K2500 camper capacity

[peegeez]

I have a 1972 GMC K2500 with a Dana 44 in front and a Dana 60 in the rear.
350 V8, SM465 & NP205 with 4.10 gears.

I have converted to discs in the rear.

The Dana 44 is rated to carry 3,500 lbs and the Dana 60 is rated to carry 6,500 lbs. For a total of 10,000 lbs. I weighed my truck at a scale and it weighs in at 4700 lbs.

So, 10,000 lbs - 4,700 lbs = 5,300 lbs
Tires and rims weigh 300 lbs so I have 5,600 lbs of capacity.

How much of that can I safely use for a camper?

The truck has been entirely rebuilt from ground up. So, everything is new and in good working order.

Any comments or info would be appreciated.

[burnin oil]

That's is the legal way to think about it. Now the actual depends on what springs are under there and how the wieght is distributed. The highest capacity is basically directly above the rear axle. Just having a camper that goes over the cab can move that wieght distribution forward alot. Also remember that if the kitchen area is on one side or is going to make it heavier on one side. Having water tanks on the opposite side can compensate but only when filled. Just some things to think about.

[Caddylackn]

What is your GVW on your tag on the door jam say? Or your registration?

If you get weighed and you are over your GVW factory rating, you get fined regardless of what you did to your truck to upgrade in this state.

If you door jam tag says 7,500 GVW, than you can go up to 7,500# which includes vehicle, your load, and passengers, and fuel.

If you budget 400 lbs for passengers and fuel, than you can be legal with a load of 2,400#s. You would be pushing it with a 10' cab over camper with water tanks full and gear unless it is a light weight model. An 8' cab over camper would be better. The cab over campers have the weight fully loaded on a tag so it is easy to do the math.

The way I see it, since there is such a large range of weights for cab overs, unless you look like you are overloaded and sagging in the back, you would probably never get pulled over and forced to weigh at a weigh station.

[jocko]

Caddylackn is spot on. GVWR does not equal front axle + rear axle capacity.
GVWR = what is on your GVWR tag.
The 72 K20 Camper Recommendations in the data book lists the Max Loaded Camper Weight as 3000 lb with the caveat that gross weight cannot exceed the GVWR of the vehicle, which, in your case, is 7500 lb (maybe, see D60 note below)

While it would require a very skinny driver, no passengers, and maybe a sippy cup's worth of gas to keep a 3000 lb camper below 7500 GVWR... I'm with Caddylackn as the max camper weight you should consider is 2400 lb.

EDIT: adding reference below - BUT, having said all that - I'd be interested in knowing what GVWR is on your tag - the D60 in the GMC may make a slight difference in GVWR. I believe 7500 lb is based on HO52 rear, which is rated at 5200 lb (below). Regardless, the axle capacity is not additive - as you can see in the example below, 3500 +5200=8700, but GVWR for that equipment combo is 7500.
Bottom line, the max your camper should weigh = (GVWR on tag) - (4700) - passenger and equipment weight
Keep in mind you had gas in the truck when you weighed it, so take into account whether you were closer to E or F.

[burnin oil]

GVW is correct but when it gets checked by DOT they will check axle loading. My comment on springs was if they will actually support the wieght, not actually the legal side of it. Around where I live it's a matter of if it fits on the trailer. You will see 3/4 ton trucks moving dozers. I am pretty sure that if you cross the border into Canada they go by axle ratings and tire capacity.


With the proper pieces installed it is possible to get the GVW raised although I don't know the exact process. My cab and chassis has that printed right on the door sticker. Final GVWR determined by upfitter.

Some states are sticklers for RVs but most are not. Just about every 40 foot RV running around being pulled by SRW is overweight. Pin wieghts always exceed the manufacturers wieght listed on the camper. Just saying. My personal opinion is to stay well under the capacity of the tires and springs since it is a high load that will tend to lean.

I would like to see a period motorhomes Gvwr. It seems that most trucks were over loaded 50+ years ago. Maybe it was just less of a concern back then.

[jocko]

Trailering capacity is a different animal - I think OP is asking specifically about a slide in camper, so GVWR calculations apply. Trailer calculations use Combined Gross Weight Rating, not GVWR (which is why you can pull a lot more on a trailer than you can haul in your truck bed).

[burnin oil]

Trailering is a different animal but you are still supposed to stay within the trucks limits. What I am trying to say and illustrate was bed wieght. Your trailer is not supposed to put anymore wieght on the rear axle than if it were the same wieght carried by the truck only. In other words 2k lbs of tongue wieght is the same as 2k lbs of bed wieght.

My k20 has 4" lift springs and 2k lbs is probably about the max I would put back there. Riding down the road is fine but it causes alot of flex and movement over the rear axle crossing a hill when off the paved road. Not talking 4 wheeling either. This is moving a water tank or a bed load of fire wood around the property type of situations.

[special-K]

I figure they make campers to sit in the bed of pickups. A 3/4t should be fine. The Dana 60 may be a tad lighter duty than an HO52 but those are what is under most C/20 and C2500 Custom Campers, if it got leaf spring option... which most did.

My comments are based on campers built back then. I have no idea what they weigh now.

[burnin oil]

Just a quick look at Lance's website and they have a 9 foot model that's right at 3k pounds. As a caution, every RV manufacturer uses base model with no options for the wieght. Each and every added feature raises the wieght but is not reflected. In a regular pull behind this could be thousands of pounds. No experience with the slide ins but I imagine it's the same. Good luck.

[tdangle]

Just for reference, my dad hauled a 10 1/2' cabover camper all over the place with (now) my 70 C20 Custom Camper. On occasion he also pulled a 2 horse trailer with 2 horses in it. Only change he made to the truck was 12.50?16.5 camper tires in the back

[peegeez]

Thanks for all of the input. The door plate does says 7500 lb GVW. So, being safe 2400 lb camper would be appropriate.

I do have coil over shocks and airbags in the rear. So I can level out the truck easily.

Anybody have any camper manufacturer's they would recommend?

Thanks

[Dieselwrencher]

Luckily in my state they only pull over and check commercial trucks. I've had 4900lbs in the bed of my truck and the only concern I would have is the tire load rating. My truck is far from stock though and my main trailer is a triple axle GN with no GVWR rating. That is a crap show. I did get pulled over with it and my 05 Dodge 3500. I was on the side of the road for 2hrs. Then a captain came along and told the officer it was all irrelevant because I was 1 not commercial, and 2, empty.

[factorystock]

Originally Posted by peegeez

Thanks for all of the input. The door plate does says 7500 lb GVW. So, being safe 2400 lb camper would be appropriate.
s

IMO, a 9' for better weight distribution and up to 2000lb max. camper would be a better match for a high center of gravity 4x4. Empty weight 4700lb, camper weight 2000lb and fuel, passengers, gear, etc up to 800lb = 7500lb max GVW.