i have a 94 awd aero with 220k km.when van is moved from park to overdrive transmission does not engage in gear,if i then select d,2,1 still nothing.however if i return to park and then select drive it will engageand cycle through all gears including overdrive.if van is stopped while driving in overdrive same issues happen[i have to put it in park then select drive].no slipping between shifts at all.any body out there have any ideas.this is my third aerostar both previous had over 350k on them when sold with no transmission or internal engine problems.

thank you

 

start by obtaining a Ford Service CD for your year
can dl here, '94 Truck has Aero
http://www.fordcds.com/
or ebay

check linkage with assistant per manual to make sure it is operating correctly with nothing slipping or loose.

do a full 10-12 qt Mercon ATF gentle flush change w. filter....search Aero forum for directions. torque valve body bolts to specs while you pan off and examine internal shifter linkage for broken or bent parts

ATF in these Aeros needs to be changed every 50k miles max.

 

These transmissions are sensitive to low fluid levels. Parking overnight on an incline will exacerbate the problem. Flush as 96_4wdr suggested then see what happens.

Testimonial: I used to poo-poo the full flush idea until last month. My son's Contour was running so poorly, I was certain the transmission was DOA. On a hunch, I ran 5 gallons of cheap fluid through, just to see what would happen. I couldn't believe the difference in operation - like night and day.