Most petrol and diesel powered forklift trucks have three pedals. They are (from left to right) inching pedal, brake pedal, and accelerator pedal.
The inching pedal acts much like the brake but it also disengages the transmission. On some forklifts this is done via a clutch mechanism, on others by a pressure valve in the transmission. Your operators manual will advise how the manufacturer recommends this control be used.
In general the inching pedal should be used when manouvering in tight places or into a load. When fully depressed (and correctly adjusted) it will hold the forklift in place and allow the accelerator to be depressed to provide lifting power to the hydraulic system. It can also be used when changing from forward to reverse to reduce any stress on the transmission.
Operators should take care not to ride the inching pedal as this causes unnecessary wear on the clutch/transmission.
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