Gearing systems for winches

General questions and answers about winches

There are three common gearing systemsused in winches, the worm gear, spur gear
and planetary gear. The main job of these gears is all the same; to gear down the high
speed motor to a low speed, high torque winch drum. The gear reduction ration is
determined by how much the motor's output revolutions are reduced for the spindle. If
the reduction is great enough the motor will have to work less and will be more efficient.
The difference in the gearing systems has more to do with their transfer efficiency.

A worm gear has a transfer efficiency of 35-40 percent. This will cause the winch to
self brake even when under a heavy load, but will require the unit to have a clutch mechanism
for free spooling. The worm gear offers the most reduction, is very reliable with build in braking
mechanism and a generally slower winching speed.

The spur and planetary gear systems have efficiencies of 75 and 65 percent respectively. What
this can mean is that they have a tendency to free spool when loaded making a braking
mechanism necessary. The planetary gears are more commonly used and provide strength and smooth
operation as well as good resistence to torque loads. Only the WARN M8274 has a spur
gear due to its different design characteristics.

General questions and answers about winches

Important things to consider when buying a winch for a truck

Types of winch gear systems

Difference between a series wound motor and permanent magnet motor

Electrical systems ability to cope with electrical winches

About receiver mounted winches

What comes with a winch when you buy it

Safety equipment needed

The reliability of a winch cable

Maintenance of winches

Using snatch blocks

Anchoring your vehicle when winching another vehicle