Serpentine belt service interval

[Smeeagain]

Can anyone tell me for an 2004 E53 3.o D Auto when the serpentine belt, as I believe it is correctly called, i.e. the one that drives the alternator, water pump and power steering pump, should be changed? I don't recall seeing any posts about this previously.

Smee

[X5Sport]

I don’t th8nk that I have ever seen reference to it either.  Treat it like a timing belt would be one approach - say every 60,000 miles/5 Year’s?

Not had it done on any of our BMWs - mind you they are all <60,000 anyway.

My X6 is in on Friday (winter tyre changeover) so I’ll try to remember to ask.

[sleepyfolk]

If you don’t know when they were last done just change them anyway, ECP have got Continental belts for very little money, I think both the belts for mine were less than £30.

Not sure if I read that 4 years or 100k was a guideline, might be wrong but seems reasonable!

[Smeeagain]

[quote="X5Sport"]
I don’t th8nk that I have ever seen reference to it either.  Treat it like a timing belt would be one approach - say every 60,000 miles/5 Year’s?

Not had it done on any of our BMWs - mind you they are all <60,000 anyway.

My X6 is in on Friday (winter tyre changeover) so I’ll try to remember to ask.
[/quote]

So to your point then, i don't think mine has a timing belt but does have a chain (and presumably with a tensioner) - any guidance on if/when the chain/tensioner should be changed bearing in mind that my car as you know is quite high mileage...?

[X5Sport]

Checked with the Dealer.....

There are no specified replacement intervals for the serpentine belt(s), however it (they) is/are inspected at each service and will be replaced if in poor condition.  Some cars have more than one apparently.

Timing chains will normally only be replaced in the event of a problem (such as a failed tensioner).  They are normally left alone for the life of the engine and never need doing. 

Cam belts are a very different approach, with some being done every 30,000 miles (depending upon engine and usage).  Cam belts are far more likely to snap!  When I worked with Surrey Police we replaced those fitted to the Ford CVH series engines of the mid-80s every 3,000 miles after a spate of premature failures destroyed certain 1600 FWD engines.  I still think of those belts as very bad technology.

[Smeeagain]

[quote="X5Sport"]
Checked with the Dealer.....

There are no specified replacement intervals for the serpentine belt(s), however it (they) is/are inspected at each service and will be replaced if in poor condition.  Some cars have more than one apparently.

Timing chains will normally only be replaced in the event of a problem (such as a failed tensioner).  They are normally left alone for the life of the engine and never need doing. 

Cam belts are a very different approach, with some being done every 30,000 miles (depending upon engine and usage).  Cam belts are far more likely to snap!  When I worked with Surrey Police we replaced those fitted to the Ford CVH series engines of the mid-80s every 3,000 miles after a spate of premature failures destroyed certain 1600 FWD engines.  I still think of those belts as very bad technology.
[/quote]

So apologies if this is a daft question - does an E53 2004 3.0 D Auto have cam belt?

Smee

[Horizon]

https://postimg.org/gallery/2q744ceye/
Images from real oem, one for the timing chain, one for the serpentine belts that drive Aux equipment i.e. Alternator power steering AC etc

[X5Sport]

BMW only use chains on the E53.