My car has 97,000 miles on it. See my signature; all upgrades are 20,000 miles or less. I'd like some experienced recommendations on replacing or rebuilding parts that are not a current problem, but are likely getting close. Things like suspension parts, wheel bearings, water pump, master cylinder.....
I'd rather fix it before it breaks than get stranded.

 

get under the car and start looking!

brakes; you're looking at lining thickness, leaks. masters usually give warning
shocks; leaks also, lower bushing condition, the upper strut top condition (they dissapear!)
bushings; pull on the wheels, hit em, any movement or clunks are bad bushings, also a prybar is helpful too
tires; how's the tread? any bumps blisters or flat spots?

its also not a bad idea to get the car aligned, and check to make sure all the bolts are tight.
none of the stuff i'm mentioning really will fail out of the blue, its more like gradual wear

 

OK. How long is a master cylinder, alternator, water pump, wheel bearings, etc. good for?

 

Master cylinders last a long time. I wouldn't bother fixing it if it ain't broke.

Same for water pump. Never had one go bad on an RX7. BMWs on the other hand....

Wheel bearings, might be time. Mine have 120k miles and I think they are getting close. Someone posted on here that they got the whole bearing and spindle from Mazda Motorsports for $80. Gotta get on that program.

If you're looking for projects, look at suspension and diff bushings. However, before you do the front A-arm bushings remember that the ball joints are not replaceable. You need to order new arms

 

Alternators are usually good for 100k plus, but some fail at 50k, some make it over 250k. You'll know when it's time, usually when your car either quits running, or everytime you go to start it, the battery is dead.