If your vehicle is a 1996 or older diesel-powered or between 8,501LBS and 10,000LBS (1997 and newer), it will be tested using either the Loaded Mode Diesel (LMD) opacity test using the dynamometer or Modified Snap Acceleration (MSA) test. The diesel tests use an opacity meter to measure the density of smoke from a vehicle’s tailpipe.
Diesel vehicles that are model year 1997 and newer and less than 8,501 lbs. will receive the On-Board Diagnostic test (OBD).
Please note: not all Test Centers can perform opacity tests. Please contact the motorist hotline or click here to find the closest Full Service Test Center.