What 393.75(d) means in plain language
FMCSR 393.75(d) prohibits operating a truck or bus with a regrooved, recapped, or retreaded tire on the front wheels. The regulation exists because steer-axle tires bear critical responsibility for steering control and braking stability—tires in that position must meet specific tread depth and structural integrity standards to maintain safe handling in all weather conditions.
A regrooved tire is one where the tread pattern has been mechanically cut back into the tire body to restore apparent tread depth. While recapping and retreading are regulated tire-repair methods that can be legal elsewhere on the vehicle, they are explicitly prohibited on the steer axle. The intent is simple: your front tires must be original equipment or factory-retreaded with full manufacturer documentation, not field-regrooved or recapped after purchase.
If you were cited for this violation, an inspector found physical evidence—usually by visual inspection during a roadside check—that your steer-axle tires did not meet this requirement.
What our enforcement data actually shows
Across our 13 million+ inspection records, 393.75(d) remains an uncommon citation. All-time, we have recorded only 2 citations for this violation. In the last 12 months, there have been 0 citations, and in the last 90 days, 0 citations. This places the code at rank #2651 of 3,036 FMCSR codes by citation volume nationally.
However, rarity does not mean low consequence. When this violation is cited, the out-of-service rate is 50.0%—meaning 1 out of every 2 citations results in the vehicle being placed out of service. This rate substantially exceeds the all-FMCSR average out-of-service rate of 31.4%, indicating that when inspectors do flag this defect, they often deem the safety risk too high to permit continued operation.
The sparse citation count reflects either strong compliance in the industry regarding steer-axle tire specification or limited inspector focus on this particular violation. Either way, if you received a citation, you are among a very small population of drivers flagged for this issue.
Who gets cited most
Our citation records show that only 2 all-time citations for 393.75(d) have been recorded in our database. Both were distributed across different carriers:
- Black Diamond Transport LLC (USDOT 1877206): 1 citation
- Victory Trans Inc (USDOT 3369401): 1 citation
With such a small sample, it is not meaningful to identify state clusters or carrier risk patterns. What this tells you is that this violation is not concentrated in any particular fleet or region—it surfaces sporadically when a driver's tire condition falls below standard during inspection.
How severe is this compared to similar codes
Within the Vehicle Maintenance category, 393.75(d) sits alongside several more frequently enforced codes. For context:
393.9(a) — Inoperable required lamps shows 660,737 citations with a 15.4% out-of-service rate. While far more common, lamp defects trigger out-of-service roughly one-third as often as regrooved steer-axle tires do.
396.3(a)(1) — Inspection/repair/maintenance - general accounts for 236,919 citations with a 45.3% out-of-service rate. This code is also subject to OOS at a comparable rate to 393.75(d), underscoring that structural tire issues are treated as serious safety defects.
393.47E — Slack adjuster defective has generated 180,363 citations but with a 0.0% out-of-service rate, indicating that slack-adjuster issues are typically correctable without removing the vehicle from service immediately.
The 50.0% out-of-service rate for 393.75(d) places it in the higher-consequence tier of vehicle maintenance violations, comparable to general maintenance and repair defects rather than minor lighting or adjustment issues.
How to avoid it
Before every trip, inspect your steer-axle tires specifically:
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Verify tire origin and repair history. Look at the sidewall markings. Original or factory-retreaded tires will be clearly marked. Reject any tire that shows evidence of field regroving (a recut pattern that appears less uniform than factory tread).
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Check tread depth with a depth gauge. Steer-axle tires must meet federal minimum tread-depth requirements (typically 4/32 inch for the front). If tread is approaching minimum, do not wait for the next scheduled maintenance—plan a tire replacement before your next inspection risk.
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Document tire condition in your pre-trip inspection form. Write down tire age (check the DOT code on the sidewall), repair method, and tread depth. This record helps you track tire condition over time and provides evidence of diligent maintenance if questioned.
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Communicate with your carrier or maintenance team about tire sourcing. If your fleet sources retreaded or recapped tires to manage cost, ensure they are factory-retreaded products rated for steer-axle use and clearly documented. Never allow field-regrooved tires on the front axle under any circumstance.
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Rotate and monitor tires proactively. Uneven wear, bulges, or sidewall cracks can accelerate the need for replacement. Weekly visual checks during fueling stops take 30 seconds and can catch problems before an inspector does.
The rarity of this citation suggests most drivers and fleets comply. If you were cited, treat it as a reset: source compliant tires, document the repair, and maintain a discipline around steer-axle inspection that becomes habit before every shift.