D5 07 model year Rattly top end
 

An interesting one this, and possibly useful for other D5 owners.
I have just bought the Missus a high mile 183k XC70 through the trade, it's a lively old thing that drives really well, everything works, gearbox is fine and even the sat nav works.......but, there's a lot of clatter coming from the top end and a deep thumping sort of noise from the air box.
I think, well, I'm fairly sure this is tired cam followers.... Anybody had a similar experience?

How old is the engine oil ??

The symptoms described might be caused by too low an oil pressure, due to a low fill or oil thinned down by fuel contamination.

If you do change the oil, use an x/40 and not an x/30, as thicker oil tends to be better for older engines.

I remember reading on here that there was a batch of so called soft cam followers used in some d5 euro 4 engines. How correct or true this is I'm can not say or how big the batch was and possible engines effected. However these engines should do 200k without problems so it could explain your problem. If you do try the thicker oil it would be interesting to hear your results tho 0 30 is what is specified for the engine.

It isnt unusual to have a rattly noise with the engine cover off , The injectors are quite noisy hence the heavy foam to deaden the sound ..

Update - further investigation has revealed some rather tired lifters and also really worn rocker bearings - everything looks fine otherwise, so I've ordered complete set of lifters and rockers - over £400 worth.... Hopefully should result in a nice quiet engine.
The rocker bearings had stacks of wear in them, so they would definetly have contributed to the noise. I think I'll run it on 0w40 fully synth for the first change and then back to Edge for the next change.
It's interesting to note the fuel consumption wasn't great, so I'm hoping that improves once the engine is back to health. Only tine will tell on that one though.

I'd heard that too somewhere, but can't remember where..

Done a few of these on euro 4 engines,

First one was when an xc70 came in with a slight misfire on acceleration and one of inlet rockers had jumped off hydraulic lifter because it had failed and gone weak,

Took me ages to find that

I've seen that one too! Had a Euro4 185 dragged in by the AA and it was exactly the same. I'm thinking weak lifters is a problem in high mikes Euro 4 engines!!

Top end all done today, new followers and lifters - she's as sweet as a nut now! Happy days.. :)

Still happy with the results? I have an euro3. Think I have the same problem maybe.