I changed mine at 2000 miles(Valvoline 5W20)and at 4000miles(Mobil 1 5W30).Mine started making the noise(rattles for about 30 to 40 seconds) after the change to Mobil1.It also started smoking on start up.It is just a little puff but it is there.I am going to change to Valvoline 10W30 tomorrow(7000 miles) and se if it helps.

 

Now that you mention it, My wife had a 1985 Golf GTI 8 valve that knocked terribly on cold start up. It had a 100000 on it when we sold it. Still ran great.