Skip to main content
Importing a Vehicle

Importation and Certification FAQs

Group 3: Trailers and Heavy Trucks

Other FAQs

The Office of Vehicle Safety Compliance (OVSC) has expanded the current Importation and Certification Division web site to include a section entitled “Frequently Asked Questions.” In this section we have attempted to address some common questions and concerns that the office deals with on a regular basis. If your question has not been addressed, please refer to Related Government Agencies for further assistance.

Trailers and Heavy Trucks

An informational brochure for new trailer manufacturers can be found on NHTSA’s website at The brochure describes all of the Federal motor vehicle safety standards that apply to trailers and identifies other requirements that a trailer manufacturer must meet before it offers trailers for sale in the U.S. If you do not have access to the Internet, we can fax you this package if you call 800-424-9393 and supply your fax number. We can also mail this package to you in the event that you do not have fax capability.

The manufacturer must request the Society of Automotive Engineers (SAE) to assign it a world manufacturer identifier (WMI) to be incorporated into the VIN the manufacturer must assign to each motor vehicle manufactured for sale in the U.S. Requests for the assignment of a WMI should be sent directly to the SAE. The SAE will confirm the assignment of a WMI to the requestor in writing. If you have questions, please contact the SAE directly at, or by calling 877-606-7323; outside the U.S. or Canada call +1 724-772-8511.

A manufacturer of motor vehicles, including trailers that are manufactured for sale in the U.S., must submit to NHTSA information needed to decipher the characters of its VINs at least 60 days prior to offering for sale the first vehicle assigned such a VIN.

Manufacturers must also submit to NHTSA identifying information on themselves and the vehicles they manufacturer to the FMVSS no later than 30 days after their vehicles are offered for sale in the U.S. Manufacturers located outside the U.S. must designate a U.S. resident as their agent for service of process.

FMVSS No. 119, “New tires for vehicles other than passenger cars,” and FMVSS No. 120, “Tire Selection and Rims for Vehicles Other Than Passenger Cars,” require manufacturers of motor vehicles to equip new vehicles with tires and rims that comply with those standards. Used tires cannot comply with a new tire standard. Under 49 CFR 573 and 577, a manufacturer that introduces motor vehicles into interstate commerce may be required to recall and remedy any vehicles that do not comply with an applicable FMVSS. Such a manufacturer may also be required to pay a civil penalty for each vehicle it manufactures that does not comply with an applicable FMVSS.

There are many sources of information.

  • Information concerning Federal safety regulations is found in Title 49 Code of Federal Regulation, Parts 500-599, available from the Government Printing Office. 
  • Interpretations of Safety Standards and Regulations may be obtained from the Internet at:
  • For trailers under 26,000 lbs, please contact the National Association of Trailer Manufacturers located in Dallas, Texas. Further information may be obtained through their website address:
  • For trailers over 26,000 lbs, the Truck Trailer Manufacturers Association, Alexandria, VA, has technical bulletins concerning many aspects of trailer manufacture. Further information may be obtained through this organization’s website address:
  • The SAE, Warrendale, PA, has customer service provisions with an extensive library of technical; information. Further information may be obtained through this organization’s website address:
  • The Recreational Vehicle Industry Association (RIVA) has recommendations about towed vehicles. Further information may be obtained through this organization’s website address:

18 U.S.C. 511 prohibits any person from tampering with a VIN that has been inscribed on a motor vehicle. If there is a typographical or computational error in a VIN that has been assigned to a vehicle by its manufacturer, the manufacturer should supply NHTSA with a list of vehicles produced with the incorrect VINs, and the VINs as they should have been inscribed on those vehicles. NHTSA will enter these VIN errors into the Federal VIN error database. 

Normally, the manufacturer will provide the owner of a vehicle with an incorrect VIN a letter identifying the erroneous VIN and the VIN as it should have been assigned, as well as a contact name and phone number to be used by law enforcement in the event that further information is needed during an investigation of the VIN error. 

Additionally, the manufacturer should inform the National Insurance Crime Bureau (NICB) of the error. That organization can be reached by emailing .

NHTSA has requirements about hydraulic and/or air brake hoses if the trailer is manufactured with either of these systems. The requirements are found in FMVSS Nos. 105 and 121. The Federal Motor Carrier Safety Administration (FMCSA) publishes requirements for commercial users of trailers with respect to brake requirements for certain weight trailers. The FMCSA regulations are found in Title 49, Code of Federal Regulations, Part 393. The FMCSA also has requirements for commercial users of trailers. Some of those requirements are for the use of tow balls, safety chains, and break-away devices.

The FMVSS have requirements for the manufacturer to use proper tires and rims for the gross axle weight rating (GAWR) and the gross vehicle weight rating (GVWR). The manufacturer may determine the GVWR by adding cargo capacity (if any) to the curb weight of the vehicle as manufactured. The wise consumer, before purchase, will determine if the vehicle has sufficient cargo capacity to carry the weight of water, additional equipment (such as televisions, and microwave ovens), and luggage. The manufacturer’s certification label must show the GVWR. The GVWR must not be exceeded by overloading the vehicle. There is little the government can do to assist a consumer who has purchased a vehicle that has insufficient cargo capacity for its intended use.