[romanonj]

Preventive maintenace wont hurt - oil, antifreeze, brake flush, diff and tranny fluid, air filter, etc.. I would check for leaks if any, and fix those. Common problems are VCG, Oil filter housing, oil pan, rear main seal. First two are very DIY'able, the other two require tools and commitment. If oil pan gasket is leaking, subframe has to come down. While its down, replace water pump and thermo. Rear main transmission has to be dropped, perfect time to replace clutch if manual. I have done both of these jobs on X3, PIA but doable.

Monitor oil consumption after oil change, and if it is excessive then you need to start tracking it down. PCV upgrade, leaks, or more serious engine wear problems

Dont listen to people on here that tell you replace your cat and mifflers?? WTF - I have never heard of that as preventive maintenance.

Suspension tune up may be needed, but I would drive it until you start feeling.hearing issues. Then upgrade to coilovers and do bushings while you are at it. No reason why you cant get another 100k out of it if it is properly maintained.