Timing belt/chain preventative replacement?

[weingarm]

My father owns a 2003 Z4 2.5i roadster with about 61,000 miles. Original owner, only adds about 2000 miles/year now. Runs great.

Keeps all the maintenance up-to-date.

Wants to know if or when he should be replacing the timing belt/chain and/or guides. I’m aware that other BMW engines have had issues with timing chains - is the 2.5i engine one to worry about?

Is there any other preventative maintenance he should be doing besides regular oil changes, brakes, etc? He’s already replaced the hydraulic pump for the power top which now works perfectly.

[Dolan]

Hey man, m54 correct? that engine has shown to be super reliable. Theres always endless things you can do to help keep it fresh.
On that engine the timing chain seems to go for however Miles you want it to. It’s very unlikely to have any problems in that area unless he’s just beating on the car all the time, or getting on it while it’s cold. Honestly even though it’s a bmw I’d say if it isn’t broke don’t fix it…it’ll show itself when it needs fixing hahaa. It seems like the car is well taken care of, I would say just make sure all the rubbers and stuff look in good shape, and keep them lubed up, and the cooling system flush/refresh (oil filter housing/thermostat gaskets replacement, to radiator, water pump) all that. Transmission fluid if you want? And spark plugs for sure should be done. If it’s running a little rough, maybe change the fuel pump filters. Again none of it is NEEDED, Until it is ya know. If you want to keep the fuel area fresh, and like you said he doesn’t drive it much, Try running some non ethanol gas it in while it’s sitting for a while and even if he doesn’t drive it, just crank it in every now and then. When stuff sits they tend to break haha. The big thing I’d say would be do the spark plugs, and the cooling system. If you are looking for something to do.

[GuidoK]

Maybe renew the guides at 200k miles just to be sure . The m54 is extremely reliable.
So with 61k miles and 2k per year, you can book an appointment for the year 2093
But seriosly, chain and guides is quite an extensive job.

The main things to look out for on a Z4 with M54 engine are:
- hydraulic roof motor. You've already done that but in the end this is a user dependant job. The roof motor dies because the drain tubes get clogged (from treeleafs etc). Keep those little drains clean. Don't park your car under trees (don't do that with any car but especially this one), best to store it inside or under a carport.
- Expansion tank of the cooling system. I would change out this part every 60k. This part is a known failure part in the cooling system, way more prone to fail than thermostat, hoses etc
- front control arm bushings/rubbers. At around 60k they will be on their way out. If you have these done at a garage, you could opt for doing the antirollbar bushings too for both the front and rear ARB.
-vanos rings. Maybe not at 60k, but more at around 80-90k miles. This is someting you have done at a quality independent BMW specialist (not a dealer!)
These rings are for sale seperately in the aftermarket for very litte (like $60 or so). The dealer can only fit a new vanos unit (expensive!)
-Disa valve. also around 100k miles. The swap out is easy, every garage can do this, or diy. New BMW valve is fairly expensive (nowadays almost $500) but there are aftermarket alternatives.
- o ring on the coolant sensor near the thermostat.
This o-ring is a known leakage point. needless to say this doesn't cost an arm and a leg...
At 60k you could think about a new waterpump.
-valve cover gasket and oilfilterhousing gasket. These gaskets are known for leaking once the cars get older, as the rubber gaskets on these parts get hard.

So for now I'd say definately the expansion tank as a precaution (a fail will often leave you stranded) and the front control arm bushings (that will give a better steering feel).