Ok,I will chime in here with my expertise as a Police officer, Motor carrier Officer AND Fatal Crash Reconstructionist.
In the State of Michigan, we are an axle weight state. This means that in commercial vehicle overweights, we measure AXLE weights, not Gross weight. It is very possible, and happens, to get an overweight ticket and be under the gross Legal weight. Attorneys like to cry the "Mis-load" to get out of the big $$$ Overweight fines, but it all falls back to AXLE weight period.
Now, with the right combination of axles, tires, axle spacing and registered elected weight, an 11 axle semi Can legally scale up to 164,000-169,000 lbs
A standard single axle dump truck with a single dual wheel axle, with no other axle within 9 ft, can weigh up to 20,000 lbs on that single axle using bridge formula weights. if that is exceeded, it goes back to Normal loading which is 18,000 lbs.
Now, tire ratings get 700 lbs per inch of width IE: 10" wide tire can carry 7000 lbs, up to the previously listed max weight. axles in series (distance between center is more than 3 and less than 9 ft get 13,000 per axle, UNLESS it is a tandem assembly (two axles with a common suspension) then they can carry 16,000 per axle. AGAIN this is mainly for semi's as if you put 18,000 on the dually rear axle, you have issues.
For small trucks, they MAY be within the state AXLE weight limits, BUT, the exceed the MFG GAWR (Gross Axle weight rating) or GVWR or GCWR. the truck can be ordered parked and off loaded as it is then an "Unsafe vehicle on the roadway"
In a traffic crash that results in a fatality or possible fatality, we impound all vehicles involved, INCLUDING, their contents. Depending on the crash, we may or may not weigh the vehicles to get their ACTUAL weights, plus try and get the occupant weights as well.
As for fault, if little Suzy or Little Billy happen to blow a red light and smash into you and they die, they will still be at fault, BUT your vehicle WILL be inspected and ANY defect or illegal combination, weights, worn brakes, vision obstruction (you know, the air fresheners on the rear view mirror) will all be noted and documented. The entire report is turned over to the County Prosecutor for review and charges. Even if not charged criminally, you could be held civilly liable.
Now, here is a little math for you all to consider, next time you overload, or consider overloading.
A little formula for Kinetic Energy
KE=1/2MV2 (KE=1/2 x M x V Squared)
M= Mass
V= velocity (feet per second)
Just for arguments, I will use MY trucks GVWR and my Trailers GVWR and combine them (9900 + 14,000 = 23,900)
According to Dodge, I can tow 14,000 lbs, BUT my GCWR (Gross Combined Weight Rating) is only 21,000 lbs the way my truck is equipped.
SO to get Mass we use this formula
(M= weight of object / g)
so (M= 21,000 lbs divided by g (g is a constant - Gravity - 32. 2)
so M=21,000/32. 2
M=652. 17
V= Velocity
Velocity is feet per second, converted from MPH
V=MPH x 1. 47 (MPH= Velocity Devided by 1. 47)
SO for this example we will use 60 mph as our base.
V= 60 x 1. 47
V = 88 FPS
So
KE = 1/2 times mass (652. 17) times Velocity squared 88 Squared (7744)
KE = 1/2 x 652. 17 x 7744
KE = . 5 x 652. 17 x 7744
KE = 2,525,252. 24 ft/lbs of energy
So basically when you are running 60 mph in your ram loaded at 21,000 lbs gross, you have the equivilent amount of energy it would require to lift a 2,525,252. 24 lb item 1 foot.
Now, take that semi loaded in Michigan at 160,000 lbs gross and it carries 19,239,735. 68 ft/lbs of energy.
Just something to think about next time you are crisng down the highway.
The standard "Over the road" tractor/trailer is grossing around 80,000 lbs OR
9,619,867. 84 ft/lbs of kinetic energy at 60 mph
You can also think about that at 60 mph, you are travelling 88 feet per secong AND that the average person has a perception/reaction time of 1. 5 seconds which means you just went 132 feet before you realized that there was a danger and reacted to it IE: braking or swerving
