Craftsman 154.37837 Operator's Manual page 13

OPERATION
Variable Drive Control
Ground speed varies with terrain, slope, grass height, etc. Increasing or decreasing
the mower speed allows you to maintain the desired speed under changing
mowing conditions. Four speeds are available, position 1 is slowest speed, position
4 is the fastest speed.
With the engine running and the blades rotating, set the drive control lever to
position 1. Push the drive control handle forward to propel the mower. Ground
speed will increase as the drive control lever is moved from position 1 to position 4
(Figure 12).
Release the drive control handle to disengage the drive when mowing around trees
and obstacles. Push the mower around obstacles for better control.
Figure 12
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