- Drive axles only
- Drive axles and somewhat on your trailer tandems
- Trailer tandems only
- Steer axle and somewhat on your drive axles
From The CDL Manual
TruckingTruth's Advice:
- The maximum legal length allowed between your trailer kingpin and your trailer tandems
- The load rating of your drive tires
- The distance between your steer axle and drive axles or "tractor length rating"
- The overall height to length ratio of the cargo in the trailer
From The CDL Manual
TruckingTruth's Advice:
- 12,000 pounds
- 12,300 pounds
- 20,000 pounds
- 34,000 pounds
From The CDL Manual
TruckingTruth's Advice:
- The tire load rating of the drive axle tires and the minimum clearance law
- The overall gross weight of the vehicle and the maximum percentage of weight on trailer tandems
- The maximum width of 8' 6" on Interstate Highways and the maximum trailer length law
- The Bridge Formula and the maximum allowed length from Kingpin to trailer tandems.
From The CDL Manual
- To prevent over-width trucks from becoming a hazard on narrow bridges
- To prevent the maximum tire load rating from being exceeded by narrow axle spacing
- To limit the weight-to-length ratio of a vehicle crossing a bridge.
- To regulate the building of bridge structures so they can support the weight of heavy modern trucks
From The CDL Manual
- To prevent overloading the trailer tandems and exceeding the load rating of the trailer tires
- To increase the minimum strength of bridges, allowing for heavier gross vehicle weights which improves efficiency
- To prevent putting too much weight on a relatively small area, causing damage to road surface and bridge structure.
- To prevent over-length trucks from becoming a hazard on narrow bridges and tight roadways
From The CDL Manual
TruckingTruth's Advice:
- When a combination vehicle makes a low-speed turn the wheels of the rearmost trailer axle follow a path several feet inside the path of the tractor steering axle.
- When making a high speed turn, the momentum carried by the trailer will cause it to swing wide and possibly outside the lane of travel
- When taking off from a dead stop, the initial torque of the engine on the drivetrain will cause a slight offtracking of the tractor which could be a hazard to other traffic
- When a trailer's tandem axles are slightly out of alignment, the rear of the trailer will track off to one side or another instead of directly behind the tractor
From The CDL Manual
- The distance from the steer axle to the drive axles
- The distance from the trailer kingpin to the center of the trailer rear axle
- The ratio of the length of the tractor to the length of the trailer
- The length of the trailer, regardless of the position of the trailer tandems
From The CDL Manual
When a combination vehicle makes a low-speed turn - for example a 90-degree turn at an intersection - the wheels of the rearmost trailer axle follow a path several feet inside the path of the tractor steering axle. This is called low-speed offtracking. Excessive low-speed offtracking may make it necessary for the driver to swing wide into adjacent lanes to execute the turn (that is, to avoid climbing the inside curbs or striking fixed objects like telephone poles).
This performance attribute is affected primarily by the distance from the trailer kingpin to the center of the trailer rear axle, otherwise known as the wheelbase of the semitrailer. To prevent trucks from being too long to maneuvering safely around turns encountered in cities and towns, the maximum length allowed from the kingpin to the trailer tandems is set by the individual states.
- 20,000 pounds
- 26,000 pounds
- 34,000 pounds
- 12,000 pounds
From The CDL Manual
The legal weight limits for each set of axles is:
- Steer axle varies by state insight(1); ?>
- 34,000 for the drive axles
- 34,000 for the trailer tandems
- 20,000 pounds
- 15,500 pounds
- 12,000 pounds
- 12,300 pounds
From The CDL Manual
TruckingTruth's Advice:
You must find the most restrictive law to determine your maximum legal weight.
The maximum Oregon allows is 20,000 pounds on the steer axle
The load rating on your tires is 6,150, which would put your maximum legal weight at 12,300 pounds regardless of the fact that there are less restrictive laws.
The maximum Oregon allows by weight is 600 pounds per inch. You have 10 inch tires so that would be a maximum of 6000 pounds per tire, or 12,000 pounds on the steer axle, which is the most restrictive of the various laws. Therefore, 12,000 pounds is your legal limit in this truck in Oregon.