Massachusetts Truck Mud Flap Law
Massachusetts requires every motor vehicle or trailer, except passenger cars, to run suitable guards that cut the spray or splash of mud, water or slush thrown by the rear wheels (M.G.L. c.90 s.7). The law sets no inch clearance and no width number. It's an equipment violation. At a roadside or scale stop an inspector checks the flap is present and works, not a precise dimension, and it's a correctable ticket, not out-of-service.
What Massachusetts makes you run
Massachusetts requires every motor vehicle or trailer, except passenger cars, to run suitable guards that cut the spray or splash of mud, water or slush thrown by the rear wheels (M.G.L. c.90 s.7). The law sets no inch clearance and no width number. It's an equipment violation. At a roadside or scale stop an inspector checks the flap is present and works, not a precise dimension, and it's a correctable ticket, not out-of-service.
Coverage and clearance
- Required: Yes
- Coverage: Guards must effectively cut the spray or splash of mud, water or slush thrown by the rear wheels; no explicit width number.
- Ground clearance: No set clearance. The statute requires suitable guards that reduce rear spray and splash (M.G.L. c.90 s.7); no inch figure and no formula.
- Fine: Equipment violation under c.90; a fine, generally a correctable ticket, not out-of-service.
Massachusetts Mud Flap FAQ
Are mud flaps required on trucks in Massachusetts?
How low can mud flaps hang in Massachusetts?
What is the mud-flap fine in Massachusetts?
Reference information for planning, not legal advice. Traffic laws change and this can be out of date, so always confirm the current statute and obey posted signs before you rely on it. Last reviewed July 2026. Source: https://malegislature.gov/Laws/GeneralLaws/PartI/TitleXIV/Chapter90/Section7. See our Terms & Disclaimer.
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