Types of Wheel Chocks | Material & Use-Case Guide

Wheel chocks come in five main types—rubber, plastic/polyurethane, heavy-duty metal, aviation, and specialty designs—each suited to specific vehicles and conditions.

Whether you’re securing a pickup on a sloped driveway or blocking a semi during a load, the right wheel chock prevents a dangerous roll. Most chocks fall into clear categories defined by material and job, though some designs work across multiple use cases. Here’s what distinguishes them and how to choose correctly.

Rubber and Plastic/Polyurethane Chocks

Rubber and polyurethane are the most common materials for general-purpose wheel chocks. Rubber chocks are economical and durable, making them the default for light trucks, trailers, and passenger vehicles. Polyurethane (often called urethane) chocks cost a bit more but resist oils, chemicals, and weather better than rubber, so they hold up longer in harsh outdoor conditions.

Minnesota OSHA guidance recognizes commercially manufactured rubber, plastic, steel, or aluminum chocks, and also permits employer-made chocks in similar shapes and sizes; wood chocks are acceptable if they meet the stated dimensions. That means material choice often comes down to environment rather than approval status.

Heavy-Duty Metal Chocks

Aluminum and steel chocks handle the heaviest loads—semi-trucks, construction equipment, and industrial trailers. Heavy-duty chocks frequently use durable polyurethane construction, but metal designs are built to survive repeated impacts and extreme weight without deforming.

For truck loading and unloading, OSHA’s standards in 29 CFR 1910.178(k)(1) and (m)(7) require wheel chocks under the rear wheels to prevent trucks from moving while workers are on the job. Commercial steel or aluminum chocks are the practical standard for this work, though wood can qualify if it meets size requirements.

Aviation and Specialty Chocks

Urethane aviation wheel chocks are built for small and large aircraft. They’re impact-absorbing, weather-resistant, and abrasion-resistant, which matters on tarmac surfaces that see constant traffic and fuel spills. The urethane material prevents sparks and damage to aircraft tires that metal chocks could cause.

Specialty categories cover the rest of the market: all-terrain utility vehicle chocks with replaceable aluminum base pads or rubber traction pads; single wedge designs for light duty; double-sided/hourglass shapes that work from either direction; tied or chained pairs that stay connected for quick placement; and foldable or spike/traction styles for muddy or gravelly surfaces. Aluminum-teeth or serrated textures help chocks grip loose ground where smooth rubber would slide.

How to Place Wheel Chocks Correctly

Proper placement matters as much as the chock itself. Place chocks snugly against the tire tread, not behind the tire’s edge or resting on top of the tire. Never use damaged or undersized chocks—a chock that doesn’t fit the tire’s curvature can’t do its job.

If wood is the only option, Minnesota’s guidance specifies lumber chocks must be a minimum of 4″ x 4″ finished approximately 3-1/2″ x 3-1/2″, with one corner beveled to fit under the tire curvature, and long enough to span both wheels in a dual set on each side of the truck or trailer.

One caveat: some chock types are application-specific. OSHA’s directive is tied to truck loading and unloading specifically, so a lightweight rubber chock that’s fine for a car may not satisfy workplace requirements. When in doubt, match the chock to the vehicle weight and the surface—and if you’re picking a set for everyday auto use, our tested auto wheel chock roundup covers the best options for typical vehicles.

Minnesota’s guidance also notes that “approved wheel chocks” can be commercial units or equivalent employer-made ones—but it doesn’t validate random improvised substitutes unless they meet comparable shape and size criteria. A chunk of 2×4 isn’t automatically a safe chock.