whats it more likely to be?

Coming up a hill earlier today box kicked down then oil drip light came on then clunking from engine, its the sound i know that is the piston is meeting the valves, what is more likely though? - Con rod or bearings or bent valves?

I know its hard to diagnose when not looking at it, noise is coming from back on right hand bank.

Don't know u mate so have to ask how much experience u have with fixing motors - just sounds like pinking to me - but please correct me if u think not.............

Oil pump u/s, followed by not so hydraulic tappets, how far did you drive it.

Have been doing my own diy mechanics for about 8 years and have good knowledge of cars its not pinking as its to loud, i do suspect oil pump has gone but unsure wether or not its valves or big end bearings?