Question: We are a truck equipment distributor looking to expand our services to routinely perform pickup box removals on a variety of trucks for local dealers. Recently, we encountered a situation where the body that a customer wants installed is wider than the non-extendable, standard outside rearview mirrors that came on the cab. Can you explain the mirror requirements in this situation?
Answer: Mirror requirements for new motor vehicles are contained in the Code of Federal Regulations (CFR) 49 Part 571.111, also known as Federal Motor Vehicle Safety Standard (FMVSS) 111: Rearview Mirrors.This standard prescribes requirements for multiple characteristics of the mirrors, including construction/dimensions, adjustability,mounting and location/field of view. Mirror manufacturers fulfill many of these requirements through product design, but final-stage manufacturers or alterers are tasked with ensuring that the correct mirrors are properly installed and mounted in a location that meets viewing requirements.
Options to Meet FMVSS Mirror Requirements
Depending on whether the pickup’s gross vehicle weight rating (GVWR) is more than or less than/equal to 10,000 lbs.,
FMVSS 111 specifies slightly different requirements.
If the truck’s GVWR is 10,000 lbs. or less, you have two options:
1. Meet the passenger car requirements contained in Section 5 of FMVSS 111, which detail performance requirements for field of view using a combination of inside and/or outside rearview mirrors.
2. Have two outside rearview mirrors of “unit magnification” (i.e., flat glass), each with at least 126 cm2 (about 19 ½ in2) of reflective surface. Additionally, this option requires the mirrors to be “installed with stable supports on both sides of the vehicle, located so as to provide the driver a view to the rear along both sides of the vehicle, and adjustable in both the horizontal and vertical directions to view the rearward scene”. (See Section 6.1(b)).
If the truck’s GVWR is more than 10,000 lbs., the mirror requirements are the same as in the second option on the lighter trucks found in Section 6.1(b), except that the reflective surface of each flat glass mirror must be larger — at least 323 cm2 (about 50 in2).
Since a number of different bodies/equipment can obscure the view from the inside rearview mirror, as well as a driver’s side outside mirror that is not intended for a wider body, the second option can be simpler than trying to determine if field of view requirements for trucks with a 10,000-lb. or less GVWR can be met. Also, original equipment manufacturers (OEMs) typically already have mirror options for trailer tow and/or “box-deleted” chassis-cab applications that are designed to meet or exceed either set of requirements and that can be used to retrofit the passenger car-style mirrors that may otherwise come on the same truck model.
For additional mirror information and guidelines for the make/model on which you are working, review OEM Incomplete Vehicle Documents and/or body builder books. NTEA members can access chassis manufacturer technical contact information in the “Technical Resources” section of NTEA.com.
Alternatives to OEM Mirrors
If an OEM mirror that would meet applicable FMVSS 111 requirements is unavailable, visit the NTEA.com “Industry Directory” to find member companies that can provide an equivalent mirror. Make sure any aftermarket mirror you consider is designed to meet the requirements for the body width your customer is requesting. Also, consider obtaining a statement from your mirror supplier indicating that the new mirrors meet all applicable FMVSS 111 requirements, provided that they are installed per the manufacturer’s instructions.
Additionally, beyond the mirrors, you may want to investigate considerations for body width, such as any OEM frontal area restrictions for the particular model you are altering and any applicable state dimensional limits for overall width.
Members can call the NTEA’s toll-free technical and engineering support hotline at 1-800-441-NTEA (6832) from 8:00am–5:00pm, Monday–Friday. We’ll be glad to assist you!