Volvo VHD - Manual (Page 199)

Fuel Economy Driving 193
Axles
An axle out of alignment will increase
rolling resistance. Regularly check the front
wheel alignment and axles on both the trac-
tor and trailer/semi-trailer. If they are
correct, there will be less rolling resistance
and, therefore, lower fuel consumption.
A good sign of an axle or wheel out of
alignment is uneven tire wear. Check the
tires often.
Engine
Faulty or incorrectly adjusted engine com-
ponents increase fuel consumption. The list
below gives some typical components that
can influence fuel consumption:
• Blocked (on the outside) charge air
cooler/radiator package
• Faulty thermostats
• Blocked fuel filter
• Blocked air intake filter
• Faulty injectors
• Dirty turbo charger
• Air in fuel system
• Faulty fuel supply pump
• Faulty fuel relief valve
• Faulty fan thermostat/clutch