Sorry, I know it's another "What oil" question has been asked million times before but could only find a few threads relating to hawk wrx.
Only last week had a genuine blue oil filter and Shell helix ultra 5w30 fully synth (as quoted in owners manual) installed but after visiting a scooby specialist, i was told that oil is "too thin" and not good for the engine.
was told to use Millers 5w40 or a 10w50 as it's winter now??
why does the owners manual state 5w30, if the oil is too thin and not good for the engine?

Hi,

Is your Hawk wrx standard or modified?

Cheers,

Guy

Hi engine wise it's completely standard apart from a Vortex catback exhaust.

Hi

I would use a 5w-40 synthetic and you will find those through the link below.

https://www.opieoils.co.uk/c-656-5w-40.aspx

Out of those, the best ones are the Fuchs/Silkolene Pro S, Millers CFS/CFS NT+, Motul Sport/300V, Red Line and Gulf Competition. The Motul 8100 X-Cess, Millers XF Longlife, Castrol Edge/Magnatec, Fuchs GT1 XTL/Supersyn, Shell Helix and Mobil Super 3000 are good, cheaper alternatives.

That's fine for all year round use in the UK.

Cheers

Tim

think it was more to do with better MPG figures

That's great many thanks.
so the Shell Helix Ultra 5w30 I put in last week, will that be fine for around 4k miles or should I just change it to 5w40 asap?
Also, between the Millers CFS and CFS NT+, what benefit will I see with the slightly higher priced NT+ over the standard CFS?
cheers

Bump
Still don't know whether to leave or change the oil?

Hi

The oil in there is fine for normal use, but if you are enthusiastic with it, the oil might thin out a bit too much.

The CFS NT+ has a higher dose of the Nanodrive additives, to reduce friction further and give better performance/economy.

Cheers

Tim

Many thanks Oilman