FORD 2000 F-550 v.1 - Manual (Page 117)

higher speeds causes the transmission to shift to a lower gear, and will
shift to 1 (Low) after vehicle decelerates to the proper speed.
Forced Downshifts
To gain acceleration in (Overdrive) or Drive (O/D OFF) when
passing another vehicle, push the accelerator to the floor. The
transmission will downshift to the appropriate gear: third, second or first
gear.
Shift strategy (4R100 automatic transmission)
To account for customer driving habits and conditions, your 4R100
automatic transmission electronically controls the shift quality by using
an adaptive learning strategy. The adaptive learning strategy is
maintained by power from the battery. When the battery is disconnected
or a new battery is installed, the transmission must relearn its adaptive
strategy. Optimal shifting will resume within a few hundred kilometers
(miles) of operation.
If the shift quality does not improve within a few hundred
kilometers (miles) of operation, or if the downshifts and other
throttle conditions do not function normally, see your dealer or a
qualified service technician as soon as possible.
MANUAL TRANSMISSION OPERATION (IF EQUIPPED)
Using the clutch
Vehicles equipped with a manual transmission have a starter interlock
that prevents cranking the engine unless the clutch pedal is fully
depressed.
Driving
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