FORD 1999 F-550 v.1 - Manual (Page 126)

Do not park your vehicle in Neutral, it may move unexpectedly
and injure someone. Use 1 (First) gear and set the parking brake
fully.
Reverse
Make sure that your vehicle is at a complete stop before you shift into R
(Reverse). Failure to do so may damage the transmission.
Put the gearshift in N (Neutral) and wait at least three seconds before
shifting into R (Reverse).
With the 5-speed transmission you
can shift into R (Reverse) only by
moving the gearshift from left of 3
(Third) and 4 (Fourth) gears before
you shift into R (Reverse). This is a
special lockout feature that protects
you from accidentally shifting into R
(Reverse) when you downshift from
D (Overdrive).
With the 6-speed transmission you
can shift into R (Reverse) by
moving the gearshift left from N
(Neutral).
1 3
2 4 R
D
R 1
L
3
4 2
D
Driving
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