Off Road & 4WD Glossary of Terms
There are currently 13 names in this directory beginning with the letter D.
Dead-Man
A dead-man is an anchor point in a winch operation. Trees or other vehicles are common anchor points, but the dead-man can be anything strong enough to remain stationary as force is applied against it.
Departure Angle
Departure angle refers to the steepest angle a vehicle can descend before the body or chassis makes contact with the ground.
Dial indicator
An instrument used for tracking precision measurements down to 1 thousandth of an inch.
Differential
The differential is a device that usually consists of gears. These gears allow each of the driving wheels to rotate at different speeds, while supplying equal power to each of them.
DOT
DOT is an acronym that stands for Department of Transportation. The 10-digit code after the DOT designation provides information such as the week and year the tire was produced, plus the manufacturer, plant, tire line, and size.
Drive Side
The Drive side of the gear refers to the convex or crowned side of the ring gear. This side of the gear is the side of the tooth that the pinion gear pushes off to turn the ring gear when accelerating forward. This holds true in all but standard rotation front differentials where it is reversed.
Drop Out
The drop out refers to a particular type of axle that has a separate gear case assembly that can be removed from the housing (picture A). This is opposed to an axle that has the gears installed into the physical axle housing (picture B).
Drop Pitman Arm
On a lifted vehicle, a drop Pitman arm can be used in lieu of a Pitman arm to fix steering issues (such as bump steer) resulting from the lift.
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