I have a EB2 with 252,500kms on the original bottom end and a 90,000k old head. I have been using 15-40w in mine as recommended and the lifters are starting to tick quite loud when its cold. What should I move it up to as I still dont quite understand oil ratings?

do you smoke drugs??

50 or 60 in an AU.... how much fuel do you want waste?

My bad, that 60 should of been a 40. Must of had that 60 stuck in my mind from Troymans post earlier

i personally use either penrite or fuchs, as these were what i used to use in my 4stroke yzf250 for years, and 250 four strokes are easy to gadge the quality of oils with. and as to the au falcons there 5-30w from memory. i personally would use the recomened oil unless you start to notice oil usage or smoke, because heavier oils dont offer more protection, infact they can increase start up wear, increase drag witch decreases fuel economy and power (dont believe me, look at cerment, the more watered down it is, the easier it is to run ur hand through). id stick to the recomended 5-30w on au+ and 10-30 on the e series. just my 2 cents

If the car is running dual fuel, which i think the original poster's AU is, would using the same grade oil as you would for petrol still be okay?

I know you can get the oils designed for cars running on LPG but if its dual fuel would you still need to use LPG oil or not?

yeah it does but they C**k up a bit with that. they need a 10/40. a few service centers changed to suit as there were some wear reported problems in the early models with the lighter oil from what Ive heard.

always run 10/40 mobil semi synth in my car (since BP canned visco).

My engine has 230,000 kms. I am using NULON 10-40 hi tech fastflow full synthetic engine oil.
I allways use NULON products i personly recon there the best.
If you have lifter noise when cold you have to use a thinner engine oil something like 10-40/50.
or you can use the NULON lifter free addative. What a product i've used it on customers cars & the feedback that i have recieved is that it realy works.
Sorry got carried away. The answer to your question is castrol. I do prefer castrol oils over valvoline any day.