Changing the belt - Roger Jones
OK, folks, opinions please. I have owned a Golf VR6 for nearly 7 years since new; I also own a 7-year old MB E320 Coupé since nearly new. I love 'em both, they're in very good nick and I shall keep them for a long time yet. The former has done 35k, the latter 40k; no, that doesn't mean constant short trips, because I don't use them unless I can do at least 5 and usually 10 miles (i.e. I actually extend local trips to warm everything up properly), and most of the miles have been either 20-mile round trips or much longer journeys. The question is, should I change the belts now? When I first raised the matter with the MB dealers who sold me the Coupé, they told me it was a chain, not a belt (they were wrong), and that it wouldn't need attention until 80k. I am nevertheless mindful of HJ's general advice on this matter in particular, so am ready to act.
Changing the belt - biggdigit
best advice is to change them as the rubber will perish with age better safe than sorry.
Changing the belt - Cliff Pope
I agree - change them.

Just a small point, but I don't think your 5, 10 or 20 mile trips are really getting the engine hot - warm yes. Try feeling the sump - is it too hot to touch?
On that regime I'd go for very frequent oil changes if you want to keep the cars - 3,000 miles with a can of flushing agent. And new coolant and engine flush every 2 years.
Changing the belt - Roger Jones
Thanks for these responses.

I do change oil frequently, although not always with a flush; the colour of what comes out is never sooty black. As for trip length, you can of course only do so much and it just isn't possible to reach optimum temperatures all the time, but I do see the key indicator -- the oil temperature readings -- get to a satisfactory level every time (i.e. they rarely get much higher on longer trips), so I am reasonably confident that good is being done.
Changing the belt --> oil temperature - Roger Jones
Further to the exchange above, I watched what happened to the oil (Mobil 1) temperature in the Golf today:

Miles Temp (°C)
2 78
3 82
4 86
5 88
6 90
7 92
8 94
9 94
10 94
Parked for 20 minutes
10 78
11 84
12 88
13 92
14 94
15 94
16 94
17 94
18 94
19 94
20 94

So it looks like it stabilizes at 7+ miles.
Changing the belt --> oil temperature - Andrew Moorey (Tune-Up)
Roger, sorry to disagree but Mercedes dont actually make an engine with a cam belt they are ALL chains and the VR6 also is chain driven.

Simplicate and add lightness!
Changing the belt --> oil temperature - NormanB
Yip and I think it is a duplex chain too. The rubber belt at the front (Poly Vee) just spins the externals....

Changing the belt --> oil temperature - Roger Jones
Many thanks for correcting me. I did have a residual doubt about that.

Value my car