Well i replaced the1-2 sccumulator piston and I am still having shifting problems.The springs were not broken.Is there another common problem with the 1997 Lincoln Mark VIII.What is my next step in troubleshooting.Please HELP

Did you do a mercon v flush, is there 12 quarts in there? Dumb questions but that's the first place that I would look other wise mine had some shifting problems when I got it rebuilt so we put a new valve body in it, and it fixed it. It turned out to be a stuck valve.

I did not do a flush I just replaced the 5qts that came out of it. I will try the flush. If that does not work is changing the valve body hard?

it not nessisary to do the whole valve body , No its not hard just remember where every thing goes. you might just have to replace a valve or some thing. just start with the flush and filter, if that dont work bring it in to a trusted trany mech and have them take it for a spin.