Motor Grader Inspection Checklist | HVI

A complete daily motor grader inspection covers two dimensions that most other heavy-equipment inspections don't have to balance equally: precision and safety. The precision trinity covers three systems that decide grade quality — the blade and cutting edge (measure wear, verify bolt torque, check end bits, inspect moldboard integrity), the circle assembly (rotation smoothness both directions, gear tooth wear, drawbar ball socket play, drift under load), and the hydraulic system (cylinder rod condition, fluid clarity, hose routing at the articulation joint, control function response). The six-zone walk-around covers everything else: front frame and steering, articulation joint, cab and safety systems (ROPS/FOPS per 29 CFR 1926.1000/1002, seat belt, horn, backup alarm, lights, fire extinguisher), engine compartment (fluids, belts, radiator screen), rear frame and tandem drive, and all six tires. The whole inspection lands in about 15 minutes when the operator knows what to look for.

Motor graders are covered by OSHA 29 CFR 1926 Subpart O (Motor Vehicles, Mechanized Equipment, and Marine Operations) when operated in construction settings. Key sections include 29 CFR 1926.600 for general motor vehicle safety requirements, 29 CFR 1926.601 for motor vehicles specifically, 29 CFR 1926.602 for material-handling equipment which includes audible warning devices such as horns and backup alarms, and 29 CFR 1926.1000 and 1926.1002 for rollover protective structures (ROPS) and falling-object protective structures (FOPS) which are required on graders manufactured after specific dates. If the grader is road-going and exceeds 10,001 pounds gross vehicle weight rating, it also falls under FMCSA jurisdiction as a commercial motor vehicle and requires DVIR reporting under 49 CFR 396.11 when driven on public roads between job sites. General duty clause requirements around fire extinguisher availability, operator training, and safe operating practices apply throughout regardless of specific subsection citation.

Cutting edge condition is inspected every shift as part of the daily pre-use walk-around, because wear rate depends heavily on material being graded and can shift quickly with a change in job site conditions. Measurement of remaining edge thickness at three points across the blade width is a weekly minimum best practice for high-utilization graders, becoming daily for high-abrasive applications like mining haul roads or heavy gravel. Bolt torque on the cutting edge is critical because a loose bolt allows edge flex during grading, accelerating wear and eventually damaging the moldboard itself — retorque per OEM interval, typically weekly, and check every daily inspection on high-hour machines. End bit condition matters as much as edge condition because once end bits wear through, the moldboard corners contact the ground directly, and moldboard replacement is roughly ten times the cost of end bit replacement. Blade cutting edge system is estimated to account for approximately 25% of grader lifetime maintenance cost when properly managed, and considerably more when neglected.

Five defects produce nearly all precision-related grade quality problems on motor graders. First and most common is circle drift under load, where the blade rotates a few degrees during a grading pass without operator input, producing a wave pattern in the finished grade that shows up only on final survey. The cause is almost always cylinder seal wear or control valve leak-by, and the daily catch is a 30-second drift test with blade lowered and engine at idle. Second is uneven cylinder response between left and right lift cylinders, causing unintentional blade tilt during grade changes; caused by fluid contamination or valve wear, catchable by lifting both cylinders simultaneously and watching for divergent speeds. Third is a bent moldboard from buried rock impact, which produces a curved edge on every subsequent pass — measurable with a straightedge across the full length. Fourth is uneven tire pressure across the six tires, which tilts the entire machine subtly enough to affect grade on long passes. Fifth is excessive play at the drawbar ball socket, which allows the blade to shift laterally under load. None of these will fail a safety inspection; all five will fail a grade survey.

Any safety-critical defect that could cause loss of control, injury, or fatal incident triggers immediate tag-out. On a motor grader specifically, that means ROPS damage or unauthorized modification (OSHA 1926.1000/1002 required for operator survival in a rollover); seat belt inoperative or damaged; frame or moldboard structural crack that could fail catastrophically under load; brake failure or dragging brake which is critical because a 40,000-pound machine loaded and moving on a grade is where brake weakness becomes fatal; steering malfunction or dead zone that makes directional control unreliable; hydraulic hose burst or major leak, both because blade control is lost and because pressurized hydraulic fluid injection injuries are catastrophic; non-functional horn or backup alarm required under 29 CFR 1926.602 on any bidirectional equipment; and missing or expired fire extinguisher, required per site policy and OSHA general duty clause. Each defect requires photo documentation, notification to maintenance, and a physical lockout tag. The grader must not return to service until repair is completed, signed off by a qualified person, and the record shows the sign-off. Digital DVIR platforms enforce this structurally by blocking dispatch until the tag-out condition is cleared.