Upshifting
For normal acceleration, Mazda recommends these shift points:

For cruising, Mazda recommends these shift points:

Downshifting
When you must slow down in heavy traffic or on a steep upgrade
, downshift before the engine starts to overwork. This reduces the chance of stalling and gives better acceleration when you need more speed. On a steep downgrade
, downshifting helps maintain safe speed and prolongs brake life.
Gear Shift Indicator (GSI)Mazda 6 Owners Manual: Control system
L.H.D.
R.H.D.
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Mazda 6 Owners Manual: Center panel module removal/installation
1. Cancel the anti-theft operation. (with anti-theft system) (See ANTI-THEFT
SYSTEM.)
2. Disconnect the negative battery cable.
3. Remove the glove compartment.
4. Remove the rear console.
5. Remove in the order indicated in the table.
6. Install in the reverse order of removal.
Caution
...