2009 9-5 Turbo Edition...Best Oil?

[highway]

I was going to take advantage of the current Halfords offer and buy some. I assumed Mobil 0/40 The web tool suggests Mobil 1 ESP 0W40 which is a fair bit more expensive. Whats best?

[WildCards]

I use Mobil 1 0W40, it's £27 at Costco

[AJLintern]

As mine drinks about a litre every 600 miles or so I use the 'Triple QX' fully synthetic stuff from Eurocarparts - used it for a few years without issues.

[jackthelad1984]

I'm the same, buy it when on offer as my aero likes to get through it. Runs fine on it.

[PAUL RUN]

last time i went to halfords and looked at oil.......i was shocked even with the special offer!!!!
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(i also get 10% Off advertised prices- through a cycle club membership)
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Amazon was half....the price....and that was delivered to my front door...
opie oils...are also much cheaper for the same oil...
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Paul.

[highway]

I've read a GM specific 5w 30 is best rather than ow 40 mobil one ?