Chevrolet 2010 Corvette Convertible Owner's Manual page 129

If you skip a gear when you downshift, you could
lose control of the vehicle. You could injure
yourself or others. Do not shift down more than
one gear at a time when you downshift.
This chart shows when to shift to the next higher gear
for the best fuel economy.
Manual Transmission Recommended
Shift Speeds in mph (km/h)
Acceleration Shift Speed
Engine
1 to 2 2 to 3
All
15 (24) 25 (40) 40 (64) 45 (72) 50 (80)
Engines
3 to 4 4 to 5 5 to 6
If the engine speed drops below 900 rpm, 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 engine performance.
See
for more information.
When this light comes on,
you can only shift from
1 (First) to 4 (Fourth)
instead of 1 (First) to
2 (Second).
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