Historical textIn force on Sept. 30, 2002Source: annual CFR editions 1996–2004

§ 393.41 Parking brake system.

Wording first on file in the 1996 annual edition, superseded by the 2005 annual edition.

govinfo, 2001 edition ↗

Compare with

Before Jan. 1, 2017 the record is one snapshot per annual CFR edition, revised as of October 1. This is the 2001 edition's wording. An amendment that took effect between Oct. 1, 2001 and Sept. 30, 2002 would not appear until the next edition, so check the citations below and the Federal Register for exact effective dates.

49 CFR § 393.41 — Parking brake system.. Text in force on September 30, 2002. This wording effective October 1, 1996 to October 1, 2005. Source: govinfo, 2001 edition, https://www.govinfo.gov/app/details/CFR-2001-title49-vol4/CFR-2001-title49-vol4-sec393-41. Retrieved from FMCSR.com, https://fmcsr.com/reg/393.41?asof=2002-09-30, on October 26, 2026. Unofficial compilation; verify against the official source.

(a) Every commercial motor vehicle manufactured on and after March 7, 1990, except an agricultural commodity trailer, converter dolly, heavy hauler or pulpwood trailer, shall at all times be equipped with a parking brake system adequate to hold the vehicle or combination under any condition of loading as required by FMVSS 571.121. An agricultural commodity trailer, heavy hauler or pulpwood trailer shall carry sufficient chocking blocks to prevent movement when parked.

(b) The parking brake system shall at all times be capable of being applied in conformance with the requirements of paragraph (a) of the section by either the driver's muscular effort, or by spring action, or by other energy, provided, that if such other energy is depended on for application of the parking brake, then an accumulation of such energy shall be isolated from any common source and used exclusively for the operation of the parking brake.

(c) The parking brake system shall be held in the applied position by energy other than fluid pressure, air pressure, or electric energy. The parking brake system shall be such that it cannot be released unless adequate energy is available upon release of the parking brake to make immediate further application with the required effectiveness.

[34 FR 15418, Oct. 3, 1969, as amended at 53 FR 49398, Dec. 7, 1988]

Amendment history

2 distinct wordings on file since Oct. 1, 1996

Oct. 1, 2005 → presentannual editions 2005–2016diff vs. previous
[70 FR 48048, Aug. 15, 2005]
Oct. 1, 1996 → Oct. 1, 2005annual editions 1996–2004viewing
[34 FR 15418, Oct. 3, 1969, as amended at 53 FR 49398, Dec. 7, 1988]

A new entry appears whenever the regulatory words change between government snapshots. Day-precise from the eCFR (2017 onward); before that, one snapshot per annual CFR edition (revised as of October 1). Bracketed citations are the Federal Register history printed with the section.