The
Dodge Towing Guide is the way to finding specific of the question.
(The
Dodge Bodybuilder Guide is the second source of this type of information).
On mine: (the closest choice set)
2004 Dodge Ram pickup 2500 SLT, QUAD CAB, 2WD, 8.0 FT Bed, 6-Speed HD Manual Transmission, 5.9L Cummins Turbo Diesel Engine - 610 lb-ft:
With 3.73 Axle Ratio Axle Ratio You Can Tow 13,100 lbs
Gross Vehicle Weight Rating (GVWR) = 9000 lbs
Payload = 2274 lbs
Curb Weight = 6726 lbs
Curb Weight Front/Rear = 4071 lbs/4071 lbs
GAWR Front/Rear = 4750 lbs/6000 lbs
Gross Combination Weight Rating (GCWR) = 20000 lbs
One takes the vehicle to a CAT Scale to find:
With driver, full fuel and items in truck that are always aboard, the "new" FF and RR axle weights plus combined numbers. This gives the proper "empty weight" to then calculate remaining payload capacity, etc. The first step in setting up a tow vehicle is to run the numbers (as is the last). While the truck is capable of higher towing numbers than those listed, one must respect tire loadings (and gamble a bit on RR axle rating; luckily commercial operators blazed this trail for us).
Proper tire pressure is about knowing the loading per wheel; generally, it is averaged across the axle. Note that combined GAWR's are higher than GVWR.
Hitch rigging is dependent on knowing proper "empty weight" as well as "hitched, but WDH inactivated" and "hitched, with WDH activated" numbers per axle [set] as it includes the trailer; the differences between axle values from solo to towing.
My truck weighs 7,360-lbs until recently, with topper, bed liner, driver, full fuel and a couple of tubs of stuff in the rear. It is now higher with full-timing load.
I'll acquire a new "empty weight", and then drag this trailer across the scales to find the other two number sets (plus trailer axle and tongue weights separately).
Start with numbers, end with numbers.
Much of what is constituted thus when we speak of longevity (component life, then vehicle life) is a matter of
getting the numbers right. Reliability is on the same curve, so to speak.
FE is more easily achieved when weight is properly distributed (bed load, and any trailer loads) so that braking and handling is least affected. This includes tire pressure numbers: derived from actual loading.
The goal, as I see it, is to
remain lane-centered going down the road with zero or very little driver input to maintain headway. Any driver input necessary to correct to this state of speed and position -- be it throttle, brakes, or steering -- is detrimental to longest life, highest reliability and thus to FE.
EDIT: The main point to working the numbers while towing is for the trailer, in a manner of speaking, to have no effect on the truck . . missed by many is that we also want the truck to have no effect on the trailer. It really is a two-way street, and the truck (when a truck is the tow vehicle) can be the weak link in the chain of road performance (which is also safety).
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