Mercedes-Benz CL 55 AMG Operator's Manual page 243

Instruments
Operation
and controls
Automatic transmission
Briefly press selector lever in the "D +" direction:
The transmission will shift from the current gear range
to the next higher gear range. If the transmission is
already in gear range "D", an additional upshift of one
gear is possible.
Press and hold selector lever in the "D +" direction:
The transmission will shift from the current gear
directly to gear range "D".
Warning!
On slippery road surfaces, never downshift in order
to obtain braking action. This could result in drive
wheel slip and reduced vehicle control. Your
vehicle's ABS will not prevent this type of loss of
control.
Important!
With transmission in gear range "D", "4" or "3",
upshifting from 1st to 2nd to 3rd gear is delayed
depending on vehicle speed and engine temperature.
This allows the catalytic converter to heat up more
quickly to operating temperatures.
During the brief warm-up period this delayed upshift
and increased engine noise might be perceived as a
Instrument
Driving
cluster display
Practical hints Car care
240
malfunction. However, neither the engine nor
transmission are negatively affected by this mode of
operation.
The delayed upshift is effective with vehicle speeds
below 31 mph (50 km/h) at partial throttle and engine
temperatures below 95 ° F (35 ° C).
To avoid overrevving the engine when the selector lever
is moved to a lower gear range, the transmission will not
shift to a lower gear, if the engine's revolutions per
minute limit would be exceeded. In this case there will
be no downshift, even when the vehicle speed reaches
the engine's rpm limit of that gear, e.g. by applying the
service brakes.
To prevent the engine from laboring at low RPM when
driving uphill gradients or with your vehicle heavily
loaded, the automatic transmission will downshift when
necessary to maintain engine RPM within the best
torque range.
Technical
Index
data