Chevrolet 1999 Corvette Owner's Manual page 84

This chart shows when to shift to the next higher gear
for the best fuel economy.
If your 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.
2-32
NOTICE:
When you are shifting gears, don't move the
gearshift lever around needlessly. This can
damage parts of the transmission and may
require costly repair. Shift directly into the next
appropriate gear.
One to Four Light (Manual Transmission)
You must complete the shift into FOURTH (4) to
deactivate this feature. This helps you get the best
possible fuel economy.
After shifting to FOURTH (4), you may downshift to a
lower gear if you prefer.
When this light comes on,
you can only shift from
FIRST (1) to FOURTH (4)
instead of FIRST (1) to
SECOND (2).
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