A quick question regarding timing belt changes and what have you. When "should" these things wear out? My car's five and a bit years old, and has covered 36,000 miles.
Is it safe to wait another year and have them changed at the six year/72,000 mile service, or should I have them done now? (And does it give any hint that it needs doing?)
The reason I ask is that when cruising at constant revs (around 3,500 - 4,000) the engine note sometimes changes for a second or so (sounds a bit strained) before returning to normal. With a rebuild at £2k, I'm getting paranoid!