I would greatly appreciate any advice!

Situation:
I have a 1998 Grand Marquis at 95K miles which has been *extremely*
reliable so far.  I love not having a car payment :) and this thing is
great for trips.  It clunks occationally around turns and over bumps and
the suspension and steering seem somewhat loose.  Acceleration is decent
but hesistates up until about 20 mph, then it gets going.  Pings pretty
bad in warm weather on 87 gas.  I've kept up on routine maintenance
(engine and transmission oil changes, radiator flushed, etc).

Question:
How long can I reasonably expect this car to be reliable?  Are there any
major things I should replace if I'm looking to keep this car for a
while longer?  Or, should I just keep up routine maintenance and replace
parts as they break?  I'll have to pay for any major service that needs
to be done since I'm no mechanic.

Specifically I'm thinking about the suspension:  I've heard a bad
suspension can burn off the tires; should I get it fixed or just buy
cheapo tires from now on?

Thanks
-- Joel