Help Understanding How Factories Detemine Truck Weights

[milo]

Posted this in 2 truck forums, got several replies but haven't gotten an answer to how they determine that yellow sticker weight, so I thought I'd post here where all the experts reside. Help me understand..... How do they determine truck weights in addition to just putting it on a scale.
My '13 XLT Screw HD Eco came with the yellow sticker saying it has a 2172 payload capacity & it has a GVWR of 8200 lbs. According to the sticker, 2172 - 8200, the truck weighted 6028 lbs when it left the factory. I took it to the only scales within 130 miles (sand & gravel scales) right off the lot the same day. Full tank of gas (36gal) and me (220#) and no dealer added extras. The weights were front axle 3520, rear axle 2680, total was 6200 lbs. That's a 172 lbs difference. Now that only leaves 2000# of payload not 2172 the sticker says. ?????
How did they determine that this truck only weighed 6028 lbs at the factory? Do they have a body that only weighs 150 lbs in there driving and only 19.5 gallons of gas? Cuz adding the other 70 lbs of body and 16.5 gallons of gas would add the other 172 lbs. Mystery to me.


Milo

[boogie_4wheel]

Manufacturers usually figure driver weight of a 14 year old girl, and use a scale that is probably a little more accurate than the quarry down the road.

I've had my current truck on 3 different scales (rock yard, at the dump, and highway inspection), and the difference was in the hundreds of pounds. I took my previous truck ('97 half ton GMC) to a local $5 scale and it weighed 7200 empty, went to the CAT scale at the truck stop the next day and it was 5900 (me, full fuel, in bed tool box, and fiberglass camper shell). The CAT scale said 6700lb hitched to my trailer, which was still less than the other scale said I was empty.

To have one vary a couple hundred pounds is no big deal (to me). There will be a percentage of error, and a light duty truck will be hard to read because you are pulling onto a scale that has the ability to read in excess of 25k pounds per axle or pad.

[rhagfo]

Well I sure hope the 172# isn't going to kill your plans, but you could load the rear axle to the Max, but that is only 2,160#. Sure not much wiggle room even in a max/max F150! :S

If I loaded my Ram, to the rear axle rating, I would be about 1,500# over GVWR. :B

[camp-n-family]

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