need sanity check on weight calcs

mkirsch wrote:

Beau Bo wrote:

mkirsch wrote:

Common practice in the TC community is to ignore GVWR and use axle ratings as your limits. That typically gains you another 1000-2000lbs of payload capacity, so you're no longer "overloaded."

Can payload capacity for rear axle be calculated or must the actual weight of the truck be measured on rear axle.

9750 is listed RAWR if that helps. I've read elsewhere that the rear axle weighs about 3500 lbs but I don't know if that includes body/suspension or just the axle. Also I don't know how to estimate the % of weight (TC/Stuff/people) that is on the front axle as opposed to the rear.

Payload capacity is RAWR - actual weight of rear axle on scale.

Best to have it weighed, but you can get by with conservative estimating.

3500lbs would be what the scale reads when you parked the truck's rear axle on the pad. That is the weight of the tires, axle, springs, and any part of the truck's frame and body that is resting on the rear wheels. 3500lbs is a bit on the conservative side. Your typical DRW truck will be a bit lighter with stock tires.

In your case it would be 9750-3500=6250lbs.

On estimating how much goes to the front vs. the rear, as a general rule nearly all of the camper's weight rests on the rear axle. Sometimes MORE than the camper's weight ends up on the rear axle if the COG of the camper is behind the rear axle.

As a rule of thumb you can put the weight of the camper on the rear axle, and the weight of anything in the cab on the front axle when you are estimating. While this is not exactly how it works, it is close enough for our purposes.

Very helpful description, thanks. So, to continue conservative estimating - assume my truck weighs 3500 on the rear axle (9750 RAWR) With the math you show, my available payload (rear axle) is 6250 lbs. I can ignore the 500lbs I assigned people and dog since they are on the front axle. This leaves me with the wet camper (4463) hitch and tie downs (200), tongue weight (700) and other stuff (500) which totals 5863 or 387 lbs under axle limit. If this is a good accurate, conservative estimate I feel a lot better about things.

As to the tires/wheels, towpro pointed out earlier that the tires are rated at 10,000. Can I assume that the stock wheels are also capable of carrying 10K? If so it seems I'm good to go, right?