So my Z is about to reach 100,000 miles

[chapeau]

My car is 20 years old this year and just about to tick over 100k. Apart from keeping the oil change services regular and addressing any problems as they arise is there anything I should have already replaced or should be replacing in the near future to avoid any major expensive issues in the future?

I'm aware the engine is meant to be quite strong (M54 2.5i) and has had the vanos replaced recently is there anything else that should be done?
I've heard people change the gearbox oil is that a necessary thing or just a nice to have?

I'm by no means a mechanic, although have changed the starter motor as that was just a few bolts, so anything beyond the basics would mean a trip to a garage to be done.

Open to opinions and ideas.

Thanks all.

 

[BumpyZ4]

I would change the gearbox fluid and the differential fluid.

 

[Zedebee]

Unless they were changed in the last 30k or so, the suspension is likely to be sh4gged. There are still cars bouncing around (literally) on their original suspension with no damping.

Shocks first, then control arms, then sub-frame bushes if you’re feeling brave.

 

[Dr. Zed]

Have you done your water pump, belts, coolant reservoir and pulley? I'd recommend you do this if not.

 

[jp_haus]

In the middle of replacing my starter right now. Straightforward job but very tight space. Waiting on the bolts to arrive before I can finish it up.

Anyway, +1 for ensuring the coolant reservoir (expansion tank) is swapped out if it hasn't been. That was the first major thing to go wrong with my Z and they're known to fail as you may be aware. It's not necessarily a "100k mark" item but preventative maintenance I would highly recommend