Volvo FM Handbook page 167

156 Driving
When changing gear it is possible to skip a gear
position if the total weight and general driving
conditions permit it.
Range control:
H High Speed Range
L Low Speed Range
Note!
If the air pressure is too low the
range gear can become stuck in
neutral. The gear lever is then locked
into neutral. The gear lever can be
moved when the air pressure
increases.
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