Driving With An Automatic
With certain automatic overdrive transmissions,
towing – especially in hilly areas – may cause
excessive shifting between overdrive and the next
– To eliminate this condition and achieve steadier
performance, overdrive can be locked out (see
vehicle Owner's Manual)
– If excessive shifting does not occur, use overdrive
to optimize fuel economy
– Overdrive may also be locked out to obtain
engine braking on downgrades
– When available, select Tow/Haul Mode to
automatically eliminate unwanted gear search
and help control vehicle speed when going downhill.
Straight from the Expy manual.