Sorry if I am re-posting.

I have a 1989 Aerostar Eddie Bauer 3.0L with about 135K on it. One day while driving it, the transmission started to shift very abruptly from a stop. The engine would race for a second, but then there was this sudden jerk. It was like if someone had kicked it forward. It had also slipped from 2nd to 3ed gear for a while. But now, it semens to run normal now. I checked the AT fluid, and it was full.

My basic point here is, since this van has passed 120K miles, should I be worried about the transmission? How would I know when ithere would be signs for a overhaul? Can it fail at any time?
Thanks!

 

the ATF should be translucent titty pinkish/red with very little dirty color and almost no smell or odor.
if it smells burnt, is dirty brown or blackish or has more than 50k miles on it, change now
search the forum for filter change and gentle flush with 12 quarts of new ATF
use DextronIII/Mercon only in a brand name not one of the cheapy store off brands.
Chevron Isosyn, Valvoline, Castrol, Pennzoil are all good.
change every 50k miles or when burnt or dirty color

most only live 120k >200k miles before rebuild. some do go longer