I have an 08 Crown Victoria Police Interceptor with 170.000 miles on it . My transmission fluid is a reddish brown but clear . The car shifts great . Should I change the fluid and filter?

Do you plan on keeping the car for the next few years? Then I would change it if you know it hasn't in awhile. The transmissions that have their fluid changed when brown and develop problems is because the transmission was on the way to begin with due to not changing.

I use an old shop vac and suck out the old with a hose sent down the dipstick tube , clean it first so you can see if any metal comes out ., The filter has a large surface area so it's not like it'll readily clog . even if you drop the pan you never get it all and the "purge " system that does has been frowned upon

This sounds like a great idea. Thank you so much!

I would change it, drive it for a day and change it again.

Change it, I had a 2001 Grand Marquis with 160K, the fluid change was overdue and the fluid was brown. I changed the fluid, never had any issues.