GMC SIERRA 1994 Manual page 85

Manual Transmissions- Shift Speeds
If you have a five-speed manual transmission (with low gear), this chart
shows when to shift to the next higher gear for best fuel economy.
Recommended Shift Speeds
-
Five Speed
Manual Transmission with Low Gear*
Engine (VIN Code)
4.3L V6 (Z)
5.7L V8 (K)
4.3L V6 (Z)
Acceleration Shift Speed MPH
(KM/H)
15 (24)
15 (24)
40 (64)
25 (40)
Cruise Shift Speed MPH (KM/H)
25-40
(40-64)
50 (80)
40 (64)
45-50
(72-80)
*L (low) is intended for use with heavy loads and is not recommended for
normal driving
If your speed drops below 20 mph (32
km/h),
or if the engine is not running
smoothly, you should downshift to the next lower gear. You may have to
downshift two or more gears to keep the engine running smoothly or for
good performance.
NOTICE:
If you skip more than one gear when you downshift, or if you
race the engine when you downshift, you can damage the engine,
clutch or transmission.
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