What oil should I put in my valver?

I use Shell Helix 15/40 and always a genuine filter

 

Any reason for that GVK? like you get it cheap or that its good?
Edited by: daveybwoy

 

is that 'borrowed' shell helix oil gary?

i've used all kinds...
Vauxhall semi 15/40W
Castrol magnatec 10/40W (?)
Quantum silver 10/40W
Castrol GTX 15/40W

got to say vauxhall was crap! tappet noise ahoy!
couldn't really tell any difference between magnatec and quantum....

 

My 8v's been in the family from birth, it's had quantum silver and a vag filter every 6000, current mileage 157000.

 

Castrol is shit, full stop. They can sue me, I can prove it. I quite like mobil one but not on an old engine. Synta gold for a turbo, Synta silver for a non-turbo. And no additives at all.