I have a 1989 E350 conversion van with a FI 460 with the AOD transmission, 4.10 axle and heavy duty tow package. The van has 105K and is in great condition. I tow a 22' enclosed car trailer and except for a little wind buffeting from passing trucks it works great. Recently while having the oil changed it was pointed out to me that the tranny fluid was getting a little dark. So it's time for a change.
My question is should I replace the fluid with dino oil or should I replace it with synthetic? Either way I would have the torque converter fluid changed as well. What has everyone's experience been with this? The tranny shifts well, with just an occasional shutter going into OD.

Thanks
Randy

 

its already been 105 thou on dino oil so why switch now