I'm still struggling with the diagrams in the truck camper loading document. I must be thinking of something incorrectly as I can't make sense of them with GT-Jim's numbers....
First, I see this diagram (from the link above)....
(click to enlarge)
So basically we're trying to determine where the shaded box (the "CG zone") is for GT-Jim's truck via his A and B dimensions.
And if we're interested in where the CG zone falls over the axle, we also need to know where the axle is. That same document has this table...
I assume GT-Jim has the double-cab and 6'6" bed so his C dimension would be 43.6".
Applying his A dimension of 33", a B dimension of 0", and a C dimension of 43.6" appears to put the entire CG zone behind the rear axle, doesn't it? If the front edge of the zone is 33" from the rear of the truck and the axle is 43.6" from it, the front edge of the zone is 10.6" behind the axle. And a B dimension of zero says the aft edge of the zone is at the tailgate. So much for keeping the COG ahead of the axle! (That doesn't make sense so I'm either doing something wrong or there's something else at play here.)
Also-
I called up one of my brothers to ask about his 2015 Silverado 1500, just to get another sample. His glovebox sticker says CWR=949#, A=66", B=28". The 2015 version of the truck camper loading document says his C dimension -- the axle--- is 38.9" forward of the bed's back end.
Now those dimensions make a lot more sense to me. The front of the shaded area would be 27.1" (66-38.9) ahead of the axle and the rear 10.9" (38.9-28) behind it. At least the CG zone is over the axle when I use his numbers!
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