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Interpretation ID: 16859.wkm

Mr. Donald L. Busey
Director of Dealer Services
Pennsylvania Automotive Association
1925 North Front Street
Post Office Box 2955
Harrisburg, PA 17105-2955

Dear Mr. Busey:

Please pardon the delay in responding to your letter to Walter Myers of my staff in which you asked whether a tractor that is converted to a straight truck is required to be equipped with an antilock brake system (ABS) as required by Federal Motor Vehicle Safety Standard (Standard) No. 121, Air Brake Systems (49 Code of Federal Regulations (CFR) 571.121). In a telephone conversation with Mr. Myers on April 3, 1998, you stated that the trucks in question are new Mack tractors equipped with 3 axles with a 4th new axle normally added in the conversion, and that most are converted to dump or cement trucks.

By way of background information, Chapter 301 of Title 49, U. S. Code (hereinafter Safety Act) authorizes this agency to establish Federal motor vehicle safety standards (FMVSS) for new motor vehicles and new items of motor vehicle equipment. The Safety Act establishes a self-certification system under which manufacturers certify that their products comply with all applicable FMVSSs. This agency enforces the standards after the fact by purchasing vehicles and equipment and testing them for compliance with the standards. The agency also investigates defects relating to motor vehicle safety. If the vehicles or equipment pass, no further action is taken. If they do not pass, or if a manufacturer or the National Highway Traffic Safety Administration (NHTSA) determines that a noncompliance or a safety-related defect exists, the manufacturer must notify the purchasers of the noncomplying or defective product and remedy the problem at no expense to the consumer. Any manufacturer that fails to provide notification of or remedy for a noncompliance or defect may be subject to substantial civil penalties.

NHTSA considers that a motor vehicle or item of equipment is "new" from the date of its manufacture until its first retail sale. Vehicle manufacturers are required to certify that each new vehicle they produce complies, as of the date of manufacture, with all then-applicable FMVSSs. In this case, if a new tractor is converted to a straight truck prior to the vehicle's first retail sale, the company making the conversion would be considered an "alterer" under our regulations. A person who alters a previously certified new vehicle must further certify that the vehicle as altered continues to comply with all applicable FMVSSs. See 49 CFR 567.7 (copy enclosed).

Subparagraph S5.1.6.1(a) of Standard No. 121 requires single-unit vehicles, including "straight trucks," manufactured on or after March 1, 1998 to be equipped with ABS that directly controls the wheels of at least one front axle and the wheels of at least one rear axle. Other axles on the vehicle may be indirectly controlled by the ABS. With respect to truck tractors, subparagraph S5.1.6.1(b) requires that truck tractors manufactured on or after March 1, 1997 be equipped with ABS that directly controls the wheels of at least one front axle and those of at least one rear axle, with the wheels of at least one axle being independently controlled. Again, other axles may be indirectly controlled by ABS.

Under Part 567, an alterer of a tractor manufactured on or after March 1, 1997 must allow the original certification label required by Part 567 to remain on the vehicle, and shall affix an additional label to the vehicle certifying that the vehicle conforms to all applicable FMVSSs affected by the alteration and in effect on a date no earlier than the original date of manufacture nor later than the date the alterations were completed. Thus, if a tractor is altered to a straight truck, the alterer must certify that it meets all applicable FMVSSs for straight trucks as of a date no earlier than the date of manufacture of the tractor nor later than the date of completion of the alteration, or any date in between. If this date is before March 1, 1998, the straight truck would not be required to be equipped with ABS. Further, if either the gross vehicle weight rating or any gross axle weight rating, as altered, are different from those shown on the original certification label, the alterer must provide those modified values.

Also enclosed for your information are fact sheets entitled Information for New Manufacturers of Motor Vehicles and Motor Vehicle Equipment, and Where to Obtain NHTSA's Safety Standards and Regulations.

I hope this information is helpful to you. Should you have any further questions or need additional information, feel free to contact Mr. Myers at this address or at (202) 366-2992, or fax at (202) 366-3820.

Sincerely,
John Womack
Acting Chief Counsel
Enclosure
Ref:121#VSA#571
d.5/13/98