Does my 5 Series BMW require timing chain replacement, and can I change the transmission oil?

I own a 1998 BMW 523i Touring (E39) currently with 97,000 miles on the clock with full service history. Presently the car is maintained by an ex-BMW technician. I'm informed the timing chain doesn't need replacing, is this correct? Also, I understand the transmission is a sealed unit, but it's starting to get noisy. Can the transmission oil be changed regardless?
The timing chain doesn't need changing. If it does, then the cost is so great that you might as well scrap the car, but I have never ever heard of a BMW needing a timing chain. Transmission - is it manual or auto? If manual, the oil can usually be changed by siphoning it out of the speedo drive aperture. If auto, the job needs to be done by a specialist, by dialysis, and has to be at the right temperature and pressure. You need a member of
Answered by Honest John on

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