The state of California requires all tractor-trailer combinations to meet the King Pin to Rear Axle (KPRA) law. What does that mean to professional drivers? The center of the rear axle on all trailers must be at the 40-foot mark or shorter and must not weigh over 34,000 pounds on the trailer axles.
HOW TO MEASURE?
- Measure 10 ft from the rear of the trailer and make a mark with tape or pen. Do not include the hinge or any other part of the trailer.
Slide the tandems to the 40-foot mark. Weigh the tractor and trailer, making sure you do not exceed the 34,000 lbs maximum on the tractor drive axles or the trailer axles.
Company policy requires you to complete scaling of the load within 15 miles of the shipper in case the load has to be reworked at the shipper. This applies even if you are relaying the load to another driver.
Please drive safely and obey each state's laws!
Source: Here