Understanding COG

jimh425 wrote:
I think you are likely making this harder than it needs to be

x3

Boatycall wrote:
X2... Yer really overthinkin this... Get a long bed truck, put a camper in. Put beer in camper. Tie it down with Torklift Tiedowns. Put dog in truck. Leave.

x2

OP wrote:
But where do you take the measurement on your truck?

Most trucks that are approved for camper hauling will have a booklet listing the points of measurement to determine the longitudinal position for the COG point of the camper. This range of distance varies according to the trucks configuration, ie; cab type, seating type, engine type, etc. Use the info in the booklet that comes with the truck or find it online from the manufacturer. Anything, else is just guessing.

ryoung

I no longer own the truck and TC in my signature.

Back of cab to center of rear axle is the standard that truck manufacturers use when they list the cab to axle measurement of cab/chassis trucks.

The 2 common, industry standard cab to axle lengths for cab/chassis trucks are 60" and 84".

For pickups, the industry standard cab to axle length for longbed pickups (8' bed) is 54".

Short bed pickups (6' to 6-1/2' bed) vary from about 32" to 38", as there is no consistent industry standard for shortbed pickups.

Bed lengths for 60" c/a chassis trucks range from 8' to 9-1/2'. Bed lengths for 84" c/a chassis trucks range from 10-1/2' to 12-1/2'.

Truck campers' center of gravity points are measured from the front lower wall of the camper, rearward. This starting measurement point will be a few inches behind the truck cab when the camper is installed on the truck, because there is a gap between the cab and front of the camper, of anywhere from 3 to 6 inches, typically.

The further forward the camper COG, the better the truck will handle the load.

Kayteg1 wrote:
When I bought my 4400 lb camper, I went to pick it up with my SRW flatbed.
The flatbed was 7-6 long, but truck was short bed and the camper overloaded my tires by 15 percent, even I anticipated that and moved spare wheel to front bumper.
I made it home OK, but bought dually right after.
So yes, COG is very important if you want to use camper with SRW.
Builders don't pay much attention to COG. On my camper all heavy stuff like batteries, generator, propane tanks are in the rear of the camper.
Holding tanks are under rear bumper, 6 -7 feet behind rear axle.
Only fresh water tank is on front.
Before I bought dually I played with COG. Removed the generator, removed one of the propane tanks, moved the batteries on front of of the flatbed, on side of the camper.
That can make about 200 lb difference on rear axle, but unless you mount front platform and put heavy stuff on it, there is not that much you can do.
Again, moving spare wheel on front bumper makes the biggest difference.

I PM'd you

JJ

mkirsch wrote:
I believe that Lance specifies their COG a bit differently. They measure from the "contact point at the rear of the bed" forward, or something like that.

They used to but the last few years they now measure like everyone else does, from the front. So it depends upon the model year.

When I bought my 4400 lb camper, I went to pick it up with my SRW flatbed.
The flatbed was 7-6 long, but truck was short bed and the camper overloaded my tires by 15 percent, even I anticipated that and moved spare wheel to front bumper.
I made it home OK, but bought dually right after.
So yes, COG is very important if you want to use camper with SRW.
Builders don't pay much attention to COG. On my camper all heavy stuff like batteries, generator, propane tanks are in the rear of the camper.
Holding tanks are under rear bumper, 6 -7 feet behind rear axle.
Only fresh water tank is on front.
Before I bought dually I played with COG. Removed the generator, removed one of the propane tanks, moved the batteries on front of of the flatbed, on side of the camper.
That can make about 200 lb difference on rear axle, but unless you mount front platform and put heavy stuff on it, there is not that much you can do.
Again, moving spare wheel on front bumper makes the biggest difference.

Thanks for all the replies,
And in a perfect world I'd get a 5500 put a flatbed on it and continue to march with the camper of my choice. But don't know what will be available and fit the budget so and yes I will pick the camper then get a truck that will haul it safely, Just saw a few interesting custom rigs and was exploring that route.

JJ

If you want to know where the COG will end up, pick a common point of contact to measure from.

Let's say the COG is labeled 48" back from the front wall of the camper. Add the thickness of the bumpers, say 3", which makes it 51" back from where the bumpers on the camper contact the front wall of your truck's bed.

So you would measure from the front wall of your truck's bed back 51", and that's where your COG would lie in the truck bed.

I believe that Lance specifies their COG a bit differently. They measure from the "contact point at the rear of the bed" forward, or something like that.

Ultimately COG is not all that critical. Even a 5000lb camper with the COG 6" behind the rear axle of the truck will only have the effect of a trailer with 500lbs of tongue weight.

Even my short bed camper fits fine on a long bed flat bed.

Boatycall wrote:

jimh425 wrote:
I think you are likely making this harder than it needs to be

X2... Yer really overthinkin this... Get a long bed truck, put a camper in. Put beer in camper. Tie it down with Torklift Tiedowns. Put dog in truck. Leave.

OP -- I get the impression from your last line you have neither the truck or TC yet. If that's the case, go out and find the TC you love, then get the appropriate truck to haul it. If it sags in the rear, it has little to due with COG, you have to add spring capacity....within reason. Don't under-truck it and get a Host Mammoth and an F150.
If you go the other route... Get a truck first, you may find a bigger camper than the truck can haul.

Could not have said it better myself.......good advice!!