big knocking noise, occasionally!

[markandsam]

Got a vr v6 done 200,000kms, change oil regularly etc, lately have noticed when its been driven for a long period , & hot , there is a knocking noise coming from motor, sounds like noisy lifters , but only does it when its fairly warm. Any suggestions , or have i answered my own question & should i just put some lifter stop noise through the oil or what??
or could it be somthin worse??

[hako]

Probably just piston slap or wrist pin knock - either can be evident on a hot engine and the sound will come and go, sometimes louder then quiter then louder - it's usually noticeable at idle when hot...no real drama. You should be running 20W50 oil - anything thinner will invite rattles. Lifters that tap usually tap hot and cold so it's probably not that although adding some lifter quitener cannot do any harm (it just thickens the oil)
At your mileage the motor should still not be using any oil between changes but it is getting on and you've got to expect some noise from the engine but I wouldn't worry about it unless it changes dramatically.
Good Luck.