Regulations for Tandem Trailers

Tandem trailers are regulated by both federal and state government.

Longer combination vehicles, or LCVs, consist of a truck tractor and two or more trailers, with a gross vehicle weight over 80,000 lbs. A tandem LCV, also called a double, is a tractor hauling two trailers.

LCV Equipment

All physical equipment, such as brakes, air systems and tires are regulated by the U.S. Department of Transportation's Federal Motor Carrier Safety Administration. All safety standards set forth by the FMCSA for single trailers also apply to individual trailers being operated as tandems or triples.

Driver Qualifications

All semi-truck drivers are required to have a commercial driver's license, or CDL. Under CFR 383.93(b), a driver operating LCV doubles or triples must also have the related CDL endorsements issued by the state in which he is licensed.

State Regulations

In addition to federal LCV regulations, there are also state regulations that must be followed. LCVs are banned in 26 states. Some of the other 24 states allow doubles, but not triples. The states that do allow LCVs have specific regulations for maximum length, gross vehicle weight and road restrictions.

References

• U.S. Department of Transportation: FMCSA, Part 658.5: Definitions
• U.S. Department of Transportation: Minimum Training Requirements for LCV Operators
• U.S. Department of Transportation: Part 658, Appendix C

Resources

• Longer Combination Vehicle Safety Data Collection
• U.S. Department of Transportation: LCV Driver Training, Required Knowledge and Skills