GMC 2003 C4C042 Owner's Manual page 112

Eaton Fuller Five and Six-Speed
Transmissions and TTC Spicer
Seven-Speed Transmissions
These transmissions have gears that automatically
synchronize when you shift up or down (except
FIRST (1) gear on the five
transmission which is unsynchronized). Choose the gear
that will maintain the road speed you want while
keeping the engine above two
speed. When the engine speed drops below two
the governed speed, shift into the next lower gear before
your engine begins to lug. When you shift down, be sure
-
to double clutch if required.
- -
speed and seven speed
-
thirds of the governed
-
thirds of
ZF Six-Speed Transmission
-
This six speed pattern is unique to GM manual
transmissions. The transmission always repositions
the shift lever to neutral, which is located between
FOURTH (4) and FIFTH (5) gear.
To prevent unintentional gear selections, additional
force is required to move the shift lever into
REVERSE (R) or FIRST (1). Use FIRST (1) when
trailer towing, driving with payload in the pickup box or
launching on a grade. Otherwise, start in SECOND (2)
gear. Only shift into FIRST (1) when the vehicle has
stopped moving.
Here's how to operate
your transmission.
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