Tow Trucks

A tow truck, also sometimes called a wrecker, is a vehicle used to take disabled motor vehicles off a roadway to another location in case of breakdown or collision, or to impound illegally parked vehicles on public or (more commonly) private property. Three general types are in common usage, usually based on heavy-duty pickup or medium truck chassis: more...

• Hook and chain - the oldest of these types is seen less frequently in developed countries. Chains are looped around the vehicle frame or axle, which is drawn aloft by a boom winch to rest against a pair of heavy rubberized mats so the customer's vehicle can be towed on its other axle.
• Axle cradling - evolved from the hook and chain technology to produce a large metal yoke that can be fitted under the front wheels to cradle them, drawing the front end of the vehicle clear of the ground by a pneumatic or hydraulic hoist so it can be towed.
• Flatbed - (Also called a Rollback) the entire back of the truck is fitted with a bed that can be hydraulically inclined and moved to ground level, allowing the customer vehicle to be placed on it under its own power or dragged onto it by a winch.

These are by no means exclusive, as hook-and-chain and flatbed units exist that also offer an axle cradler.

Operations

Tow trucks are usually operated by private businesses, except for major highways and toll roads, where the road authority may operate the tow trucks for that stretch of road. Businesses who operate a large fleet of vehicles, such as school bus companies or package delivery services, often own one or several tow trucks for the purposes of towing their own vehicles. Government departments with large fleets (such as the police departments, fire departments, transportation authorities and departments of public works of major cities) may similarly own a tow truck or trucks. Police department tow trucks may also be used to impound other vehicles, or in some cases to merely relocate them (eg: prior to starting emergency street repair, parked vehicles may need to be removed from the site.)

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