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轮胎要求§ 393.75 Tires.§ 393.75 Tires.轮胎要求
适用于联邦 Part 393 覆盖的货车和牵引车。本文选择常见检查项目，不替代完整出车检查、维修标准或特定车辆例外。For trucks and truck tractors covered by federal Part 393. These are common inspection points, not a replacement for the full pre-trip inspection, maintenance requirements or vehicle-specific exceptions.
轮胎同时看损伤、花纹、载荷和气压Check tire damage, tread, loading and inflation
- 具体要求What the rule requires
- 轮胎露出帘布或带束层、胎面或胎壁分离、瘪胎，或有可听见的漏气等情况时，不得继续运行。货车／牵引车前轮的主要胎纹沟深至少为 4/32 英寸，其他轮胎一般至少为 2/32 英寸；测量时须避开连筋等位置。同时应检查额定载荷，以及适合实际载荷的冷胎气压。Do not operate on tires with exposed ply/belt material, tread or sidewall separation, a flat or an audible leak. Major tread grooves on truck/tractor front tires must be at least 4/32 inch deep; other tires generally need 2/32 inch, measured away from tie bars and similar features. Also check load ratings and cold inflation appropriate to the load.
(a) (a) No motor vehicle shall be operated on any tire that—
(a)(1) (1) Has body ply or belt material exposed through the tread or sidewall,
(a)(2) (2) Has any tread or sidewall separation,
(a)(3) (3) Is flat or has an audible leak, or
(a)(4) (4) Has a cut to the extent that the ply or belt material is exposed.
(b) (b) Any tire on the front wheels of a bus, truck, or truck tractor shall have a tread groove pattern depth of at least 4/32 of an inch when measured at any point on a major tread groove. The measurements shall not be made where tie bars, humps, or fillets are located.
(c) (c) Except as provided in paragraph (b) of this section, tires shall have a tread groove pattern depth of at least 2/32 of an inch when measured in a major tread groove. The measurement shall not be made where tie bars, humps or fillets are located.
(g) (g) Tire loading restrictions (except on manufactured homes). No motor vehicle (except manufactured homes, which are governed by paragraph (h) of this section) shall be operated with tires that carry a weight greater than that marked on the sidewall of the tire or, in the absence of such a marking, a weight greater than that specified for the tires in any of the publications of any of the organizations listed in Federal Motor Vehicle Safety Standard No. 119 (49 CFR 571.119, S5.1(b)) unless:
(h)(2)(i) (i) Tire inflation pressure. (1) No motor vehicle shall be operated on a tire which has a cold inflation pressure less than that specified for the load being carried.
使用固定来源版次；适用日期与例外以原文及历史沿革为准。Uses a fixed source edition; check the original and statutory history for operative dates and exceptions.
法规原文 · 英文REGULATION TEXT · ENGLISH
轮胎要求§ 393.75 Tires.
官方来源快照；不代表已核对现行汇编及后续修订。请核对来源版本。Official-source snapshot; current consolidated law and subsequent amendments have not been verified.
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49 CFR 393.75 · § 393.75 Tires.
§ 393.75 Tires.
(a)No motor vehicle shall be operated on any tire that—
(a)(1)Has body ply or belt material exposed through the tread or sidewall,
(a)(2)Has any tread or sidewall separation,
(a)(3)Is flat or has an audible leak, or
(a)(4)Has a cut to the extent that the ply or belt material is exposed.
(b)Any tire on the front wheels of a bus, truck, or truck tractor shall have a tread groove pattern depth of at least 4/32 of an inch when measured at any point on a major tread groove. The measurements shall not be made where tie bars, humps, or fillets are located.
(c)Except as provided in paragraph (b) of this section, tires shall have a tread groove pattern depth of at least 2/32 of an inch when measured in a major tread groove. The measurement shall not be made where tie bars, humps or fillets are located.
(d)No bus shall be operated with regrooved, recapped or retreaded tires on the front wheels.
(e)A regrooved tire with a load-carrying capacity equal to or greater than 2,232 kg (4,920 pounds) shall not be used on the front wheels of any truck or truck tractor.
(f)No motor vehicle may be operated with speed-restricted tires labeled with a maximum speed of 55 mph or less in accordance with S6.5(e) of FMVSS No. 119 at speeds that exceed the rated limit of the tire.
(g)Tire loading restrictions (except on manufactured homes). No motor vehicle (except manufactured homes, which are governed by paragraph (h) of this section) shall be operated with tires that carry a weight greater than that marked on the sidewall of the tire or, in the absence of such a marking, a weight greater than that specified for the tires in any of the publications of any of the organizations listed in Federal Motor Vehicle Safety Standard No. 119 (49 CFR 571.119, S5.1(b)) unless:
(g)(1)The vehicle is being operated under the terms of a special permit issued by the State; and
(g)(2)The vehicle is being operated at a reduced speed to compensate for the tire loading in excess of the manufacturer's rated capacity for the tire. In no case shall the speed exceed 80 km/hr (50 mph).
(h)(1)Tire loading restrictions for manufactured homes built before January 1, 2002. Manufactured homes that are labeled pursuant to 24 CFR 3282.362(c)(2)(i) before January 1, 2002, must not be transported on tires that are loaded more than 18 percent over the load rating marked on the sidewall of the tire or, in the absence of such a marking, more than 18 percent over the load rating specified in any of the publications of any of the organizations listed in FMVSS No. 119 (49 CFR 571.119, S5.1(b)). Manufactured homes labeled before January 1, 2002, transported on tires overloaded by 9 percent or more must not be operated at speeds exceeding 80 km/hr (50 mph).
(2) Tire loading restrictions for manufactured homes built on or after January 1, 2002. Manufactured homes that are labeled pursuant to 24 CFR 3282.362(c)(2)(i) on or after January 1, 2002, must not be transported on tires loaded beyond the load rating marked on the sidewall of the tire or, in the absence of such a marking, the load rating specified in any of the publications of any of the organizations listed in FMVSS No. 119 (49 CFR 571.119, S5.1(b)).
(h)(2)(i)Tire inflation pressure. (1) No motor vehicle shall be operated on a tire which has a cold inflation pressure less than that specified for the load being carried.
(2) If the inflation pressure of the tire has been increased by heat because of the recent operation of the vehicle, the cold inflation pressure shall be estimated by subtracting the inflation buildup factor shown in Table 1 from the measured inflation pressure.
(j)The requirements in paragraphs (g) and (h) of this section shall not be construed to require manufacturers to add any markings to the sidewall of a tire.
49 CFR 393.75 Average speed of vehiclein the previous hour Minimum inflation pressure buildup Tires with 1,814 kg (4,000 lbs.) maximum load rating or less Tires with over 1,814 kg (4,000 lbs.) load rating 66-88.5 km/hr (41-55 mph) 34.5 kPa (5 psi) 103.4 kPa (15 psi).
[34 FR 9344, June 13, 1969, as amended at 40 FR 44557, Sept. 29, 1975; 41 FR 36657, Aug. 31, 1976; 44 FR 25455, May 1, 1979; 44 FR 47938, Aug. 16, 1979; 53 FR 18057, May 19, 1988; 53 FR 49401, Dec. 7, 1988; 63 FR 8339, Feb. 18, 1998; 65 FR 70220, Nov. 21, 2000; 66 FR 67694, Dec. 31, 2001; 70 FR 48054, Aug. 15, 2005; 81 FR 47731, July 22, 2016; 91 FR 7887, Feb. 19, 2026]
依据关联的官方原文及官方项目说明起草。中文和英文解读均为 CTAC AI 辅助工作稿，未经人工审核；教学案例不是实际会员记录。采集日期不是法规生效日期。Drafted from linked official texts and agency guidance. Both language interpretations are CTAC AI-assisted drafts pending human review; examples are illustrative, not member records. Capture dates are not legal effective dates.
车灯正常工作与反光装置不受遮挡§ 393.9 Lamps operable, prohibition of obstructions of lamps and reflectors.§ 393.9 Lamps operable, prohibition of obstructions of lamps and reflectors.车灯正常工作与反光装置不受遮挡
动力车辆应配备的应急设备§ 393.95 Emergency equipment on all power units.§ 393.95 Emergency equipment on all power units.动力车辆应配备的应急设备
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