(3.) Truck & Trailer Weight Distribution- Spread Axel VS Stretch Trailers

Spread Axel Trailers

Spread axle trailers do not have adjustable axles to shift weight so all loads must be loaded in the center of the trailer to avoid overweight issues. 

Gross Weight: Maximum of 80,000 lbs. 

Combined weight of tractor, trailer, driver, fuel, cargo, and equipment. Any truck grossing over 80,000 lbs. must have overweight permits. 

Maximum Axle Weights- Spread Axle Trailers – A truck can weigh less than 80k and still get weight violations on individual axles. The weight limits per axle are listed below. Note that spread axle trailers can be up to 40,000 lbs. but cannot exceed 80,000 lbs. gross weight. 

    12K                                         34K                                                                            20K                   20K

   Steer                                     Drives                                                                                    Trailer

Spread Axle Trailer Weight Troubleshooting Chart

ProblemSolutions
Over Gross Weight1. Have shipper remove part of load.
2. Apply for overweight permits
Over on Steer Axle1. If the truck has an adjustable 5th wheel, have driver move the 5th wheel back. Each notch should remove about 500lbs from the steer axles
2. Reload cargo more towards the rear of the trailer.
Over on Drive Axles1. If the truck has an adjustable 5th wheel, adjust the 5th wheel forward. This will shift weight from the drive axle to the steer axel. (~500lbs per notch)
2. Reload cargo more towards the rear of the trailer.
Over on Trailer AxlesCargo must be reloaded forward of its current position. 

Moving Cargo– If the weight of the cargo is evenly distributed, a 4-inch shift forward or reverse will transfer around 500lbs to the axle in the direction of that shift. 
5th Wheel Shifts– Not all tractors are equipped with sliding 5th wheels. If the weight to be shifted exceeds 2000 lbs. there will likely not be enough adjustment to fix the problem.

Stretch Trailers

Gross Weight: Maximum of 80,000 lbs 

Combined weight of tractor, trailer, driver, fuel, cargo, and equipment. Any truck grossing over 80,000 lbs. must have overweight permits. 

Maximum Axle Weights- Tandem Trailers (Stretch trailers)

    12K                                         34K                                                                                                 34K

  Steers                                     Drives                                                                                           Trailer

ProblemSolutions 
Over Gross Weight1. Have shipper remove part of load
2. Apply for overweight permits
Over on Steer Axle1. If the truck has an adjustable 5th wheel, have driver move the 5th wheel back. Each notch should remove about 500lbs from the steers.
2. Reload cargo more towards the rear of the trailer.
Over on Drive Axle 1. Have driver move tandems on trailer forward. Each notch forward will deflect 250 to 500 lbs to the trailer weight
2. Cargo must be shifted to the rear of the trailer.
Over on Trailer Axles1. Have driver move trailer tandems back. Each notch back will deflect 250 to 500 lbs to the drive axles. 
2. Cargo must be shifted forward on the trailer

Moving Cargo– If the weight of the cargo is evenly distributed, a 4-inch shift forward or reverse will transfer around 500lbs to the axle in the direction of that shift. 

5th Wheel Shifts– Not all tractors are equipped with sliding 5th wheels. If the weight to be shifted exceeds 2000 lbs. there will likely not be enough adjustment to fix the problem. 
Tandem Shifts– Only stretch trailers have adjustable trailer tandems. The amount of weight deflected per notch will depend on how far the trailer is stretched.