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Interpretation ID: 11244

Mr. Ben Ray
Route 2, Box 229-E
Savannah, TN 38372

Dear Mr. Ray:

This responds to your letter asking about Federal requirements for automatic brake adjusters on log trailers. According to your letter, you manufacture log trailers, using used axles that already have what you call "regular" (i.e., manual) brake adjusters on them. In an October 13, 1995 telephone conversation with Mr. Marvin Shaw of my staff, you further stated that the wheels, brakes, and suspension are typically used, but that occasionally you use new brake systems. You also clarified that these trailers are used on the public roads as well as in the woods for transporting logs to the mills. You asked whether it is permissible to use manual brake adjusters instead of automatic adjusters. The answer depends on whether your log trailers are equipped with new or used components and the trailer continues to use the Vehicle Identification Number (VIN) and to be owned by the user of the reassembled vehicle.

By way of background information, the National Highway Traffic Safety Administration (NHTSA) issues safety standards for new motor vehicles and new motor vehicle equipment. The agency does not provide approvals of motor vehicles or motor vehicle equipment. Instead, manufacturers are required to certify that their vehicles or equipment meet all applicable standards. One such standard is Standard No. 121, Air brake system, which requires new trailers to be equipped with automatic brake adjusters. The following represents our opinion based on the facts provided in your letter.

NHTSA's regulations specifically address the question of when trailers produced by combining new components and used materials are considered to be new trailers. Section 49 CFR 571.7(f) states that when new and used components are used in trailer manufacture, the trailer will be considered "newly manufactured" unless each of the following three conditions is true with respect to the trailer. First, the trailer running gear assembly, which includes the axle(s), wheels, braking and suspension, is not new and was taken from an existing trailer. Second, the existing trailer's identity is continued in the reassembled vehicle with respect to the VIN. Third, the existing trailer is owned or leased by the user of the reassembled vehicle.

In other words, a log trailer will generally be considered newly manufactured, unless all these conditions are met. If a trailer is considered newly manufactured, then it must comply with the

current requirements applicable to trailers. Among other things, this means that the trailer must be equipped with automatic adjusters. If a trailer meets these three conditions, then it is considered not newly manufactured and may be equipped with manual adjusters.

I hope this information is helpful. If you have any questions about NHTSA's safety standards, please feel free to contact Marvin Shaw at this address or by telephone at (202) 366-2992.

Sincerely,

Samuel J. Dubbin Chief Counsel

ref:121# 571 d:11/9/95