In my little town, we just had our 5th accident involving an overloaded trailer this year, and the first fatal accident in our town in 2 years. It was a van towing a dangerously overloaded utility trailer. The police chief/neighbor asked my opinion on what happened, and why so many accidents here involve trailers. We came to the conclusion that the van was overloaded by quite a bit. We've only had 12 accidents in town this whole year. I was a bit surprised when even a law enforcement officer with 10 years of experience didn't know how to calculate the maximum a vehicle can tow!

The basic numbers you need:

From the manual and door sticker:
Front Gross Axle Weight Rating (Front GAWR) - The rated capacity of your front axle.
Rear Gross Axle Weight Rating (Rear GAWR) - The rated capacity of your rear axle.
Gross Vehicle Weight Rating (GVWR) - How much your vehicle is allowed to weigh. This is the maximum you are allowed to have on all four tires of the vehicle itself. This means all cargo, etc.
Rated Towing Capacity - This come from your manual.
Gross Combined Wieght Rating (GCWR) - Most manuals will list this.

From a truck scale:
Actual Rear Axle Weight
Actual Front Axle Weight
Trailer Weight

Optional (tongue scale):
Trailer tongue Weight - How much weight the hitch pushes down on the vehicle with.

Are you overloaded on your tow/hauling vehicle:

Front GAWR - Actual Front Axle Weight = Reserve Capacity of Front Axle
If this is 0 or Negative, you are overloaded. If this wieght is below the empty number when you have loaded you vehicle, you are DANGEROUSLY LOADED and must shift weight forward. You might not be able to stop or steer.
Rear GAWR - Actual Rear Axle Weight = Reserve Capacity of Rear Axle
If this is 0 or Negative, you are overloaded.
GVWR - (Actual Rear Axle Weight + Actual Front Axle Weight) = Reserve Weight Capacity of the vehicle overall.
If this is 0 or Negative, you are overloaded. You might not be able to stop.
GCWR - (Actual Rear Axle Weight + Actual Front Axle Weight + Trailer Weight) = Reserve GCWR.
If this is 0 or Negative, you are overloaded. You might not be able to stop.

When we did this math on my 1995 E150 Club Wagon with Towing Package we came up with 5600lbs towing capacity. The manual says I can tow 6600. If I loaded 6600, I would be LEGALLY OVERLOADED and would be exceeding fords specifications. In my case, the GCWR was my limit. My van is 6400lbs loaded right now thanks to its huge battery bank. My 12,000 GCWR leaves me with 5600lbs of Reserve GCWR. My rear axle is also pretty close to its GAWR, and I have to leave some room for the 10-15% tongue weight of the trailer.

After we did the math on my van as an example, he did the math on the vehicle in the accident. I checked his work. With a 6000lbs of rock on the trailer, and another 6100lbs in the van the van was operating %170 overweight. It gets worse, as most of the rock in the van was secured BEHIND the back axle (just sitting in the door) per the driver. We went to the van in the lot and re-arranged the weight in the van and shifted the pallet forward on the trailer (where it slid to after the driver panic braked, it was not secured.) We re-scaled the front axle and came up with 2100lbs on the front. The rear axle was incredibly overloaded to ~13000lbs! Not much of a question as to why he lost control. His brakes were made ineffective by too low of a front axle weight. With load shift and no functioning brakes on his trailer, this went bad. The driver and passenger of the van are both fine, the death was in the car that was T-Boned.

 

That is a sad story. We had a serious wreck here with a tar pot trailed behind a 1/2 ton van. It weighed 10,000 with no trailer brakes and the van was fully loaded with tools and supplies. No total numbers but it had to be more than 200% of GVWR. Also a brake failure.

 

Loaded and over-loaded vehicles are serious business. Operating with bad weight distribution or excess weight is irresponsible. You may get away with it until something goes wrong. Something unexpected, like a distracted driver suddenly in your path. I have been lucky in that the 2 times I needed to panic stop my '95 E-150 while towing my un-braked boat trailer, there was room to stop. But I realized I was way over my GVWR of 7000 lbs. and needed more braking power. My past employer is dealing with the grief of killing a driver he T-boned while towing a skid-steer with an SUV and no functioning trailer brakes. A friend of mine is dead after swerving his loaded 18 wheel tanker to avoid a deadly crash with a PT cruiser. In both cases, it was the other driver who failed to yield to a vehicle which had the right of way. Be careful, no mater what you haul.

 

Just had the same here, a plumbing wholesaler was towing an overloaded trailer with no brakes went into the ditch because he could not stop his E-350!

Dumb!

 

These days, I do most of my hauling with the Volvo FE below. After 40 years of towing everything from broke down cars at the end of a strap to a front loader on a brakeless trailer, I can say that there is no better feeling than full air brakes on a 33,000 GVWR rig underloaded by 10,000 pounds. I did a lot of reckless things in the past for which I am sorry and I am grateful that no one was ever hurt despite my shortcuts. Today, I load that big rig like it will be flipped upside down, drive it like my grandma going to church, and pray that others do the same. A lot of sad stories come from towing and hauling mistakes.