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Section § 393.83: Exhaust systems.
Guidance Q&AQuestion 2: Does § 393.83 specify the type of exhaust system, vertical or horizontal, to be used on trucks or truck tractors?
Guidance: No.
Section § 393.83: Exhaust systems.
Guidance Q&AQuestion 1: Is a heat shield mandatory on a vertical exhaust stack?
Guidance: No. However, § 393.83 requires the placement of the exhaust system in such a manner as to prevent the burning, charring, or damaging of the...
Section § 393.81: Horn.
Guidance Q&AQuestion 2: Are there established criteria in the FMCSRs to determine the minimum sound level of horns on CMVs?
Guidance: No.
Section § 393.81: Horn.
Guidance Q&AQuestion 1: Do the FMCSRs specify what type of horn is to be used on a CMV?
Guidance: No.
Section § 393.76: Sleeper berths.
Guidance Q&AQuestion 1: If a compartment in a CMV is no longer used as a sleeper berth, must it be maintained and equipped as a sleeper berth as required in § 393.76?
Guidance: No.
Section § 393.75: Tires.
Guidance Q&AQuestion 4: Do tires marked ‘‘NHS’’ (not for highway service) mean that highway use is prohibited by § 393.75?
Guidance: No, provided the use of such tires does not decrease the safety of operations (see Periodic Inspection...
Section § 393.75: Tires.
Guidance Q&AQuestion 3: May tires be filled with materials other than air (e.g., silicone, polyurethane)?
Guidance: Section 393.75 does not prohibit the use of tires filled with material other than air. However, § 393.3 may prohibit the use...
Section § 393.75: Tires.
Guidance Q&AQuestion 2: May a vehicle transport HM when equipped with retreaded tires?
Guidance: Yes. The only CMV that may not utilize retreaded tires is a bus, and then only on its front wheels.
Section § 393.75: Tires.
Guidance Q&AQuestion 1: If a CMV has a defective tire, may the driver remove the defective tire from the axle and drive with three tires on an axle instead of four?
Guidance: Yes, provided the weight on all of the remaining tires does not...
Section § 393.71: Coupling devices and towing methods, driveaway-towaway operations.
Guidance Q&AQuestion 1: May a fifth wheel be considered as a coupling device when towing a semi-trailer in a driveaway-towaway operation?
Guidance: Yes. Section 393.71(g) requires...