Explainer

Mud varies more than any other surface. Some is a thin slick over firm ground; some is bottomless. The two look identical from a driver’s seat.

Why mud behaves as it does

Traction in mud depends on the tread clearing itself. A tread pattern packed with mud is effectively a slick tyre, which is what aggressive open-lug patterns are designed to prevent — the lugs fling material out as the wheel turns.

That is also why wheel speed can help in mud where it hurts in sand: enough rotation to keep the tread clearing, without so much that you dig.

Depth is unknown by definition

You cannot see the bottom. A rut that carried the vehicle ahead of you may be deeper by the time you follow, because each pass churns it.

Ruts also steer the vehicle. Once in them, the front wheels may be pointing somewhere the vehicle is not going, and that is how sidewalls meet rut walls.

The environmental dimension

This is where technique and access policy meet. Driving a muddy route widens it, because vehicles skirt the churned section and create parallel tracks.

Route widening and rutting are among the most cited reasons for trail closures, which is why seasonal closures exist and why agencies close routes when they are wet rather than when they are busy.

A route driven when saturated does damage that a route driven when firm does not. The federal travel management framework turns on documented resource conditions, and rutted, widened routes are exactly that documentation.

Turning back

The decision to stop is the hardest skill in off-road driving and the most valuable.

Useful triggers: you cannot see the bottom and cannot probe it; the ruts are deeper than your clearance; you are alone; the recovery would require an anchor that does not exist; or getting through commits you to a return trip you may not manage.

A vehicle that turns around is not a failure. A vehicle winched out at midnight having torn a route apart is a worse outcome for everyone, including the people who want the route to stay open.

This article was researched and drafted with the assistance of AI tools and reviewed, fact-checked and edited by Leonidas Clark before publication. Conditions and rules vary; confirm current route status with the managing agency.