Cabover truck axle load concerns

Jfet

Adventurer
I went by the truck scales with our camper on our Isuzu NRR 170" wheelbase 20 foot flatbed and got the axle weights.

Without the camper I was at 4540 lbs front and 4340 lbs rear.

With the camper I am at 6320 lbs front and 6060 lbs rear. So the camper weighs 3500 pounds (right about what I expected). It will be getting a little bit heavier when we add the sofa and some overhead cabinets, but should be under 4000.

The truck is rated for 6850lbs on the front axle so we are below that (the rear axle is some insane 13,000lbs). Tires are Toyo 225/70R19.5 M608Z drive on all wheels and rated at 3640lbs single and 3415lbs dual (so 7280lbs on the front axle).


The headache rack made up of C 4 x 5.4 (4" 1.584" 0.184" 5.4 lbs/ft) steel channel and some expanded metal sheeting. I could lop off 3 feet of the rack and still have a small headache rack stop for the camper/flatbed loads although it would not be quite as safe when the camper was off the flatbed (If for example I wanted to use the flatbed to pick up a big pile of lumber).

That would cut off 20 feet of the channel (top 8 foot bar and four 3 foot verticals) which would be 108 pounds plus probably another 20 pounds for the expanded metal.

I know that when we put stuff on flatbed behind the rear tires it will take some load off the front. We do plan to have under truck boxes and can place very heavy items (extra water, the jack stands, perhaps a 2nd fuel tank) under the flatbed aft of the rear tires.

Do you think cutting down the headache rack is worth it to save that 128 pounds? Any other ideas, opinions?


ontruck4.jpg

ontruck3.jpg
 

westyss

Explorer
doesnt seem worth it to cut off the headache rack, like you stated, loading stuff on the rear will lighten the front up so just ensure you load the truck properly and keep the heavy items behind the rear wheels.

That flat deck must weigh a ton?
 

Jfet

Adventurer
doesnt seem worth it to cut off the headache rack, like you stated, loading stuff on the rear will lighten the front up so just ensure you load the truck properly and keep the heavy items behind the rear wheels.

That flat deck must weigh a ton?

Well, lets calculate that. The truck plus flatbed minus camper weighed in at 8600 pounds dry. The body builder's guide for the 2006 NRR 176" WB states the base truck/chassis is 6184 pounds.

So yes, the flat deck weighs a bit over a ton :) Heavy bastard eh?
 

Jfet

Adventurer
so what am I missing. Seems like you are below gvw. maybe I need more coffee...

Passenger and any weight under the truck forward of the rear tires, plus I have not added the 200 pounds of 1000 watts solar panels to the roof yet. I just don't want to be too much over the front axle rating when I am not carrying anything on the rear flatbed portion. I guess I could always stack some concrete bags back there :)
 

njtacoma

Explorer
I don't have a cab over truck, and I don't know your situation.

With that, could you move the camper back on the flat bed those times when you aren't going to haul anything on the rear? Perhaps two sets of tie down points that allow flexibility in positioning the camper? It would obviously create a strange dead air space, and possibly wreck the amazing aerodynamic properties of the truck:ylsmoke: but it would move the weight back.
 
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westyss

Explorer
Well, lets calculate that. The truck plus flatbed minus camper weighed in at 8600 pounds dry. The body builder's guide for the 2006 NRR 176" WB states the base truck/chassis is 6184 pounds.

So yes, the flat deck weighs a bit over a ton :) Heavy bastard eh?

Haha, thats why I said it........I did some quick math.
 

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