Ford Focus Mk 2 2005 1.6 petrol. Will 5W40 fully synth do any harm?

[Richie616]

A colleague told me this was the best oil for my engine. Since doing the oil and filter change I am since reading that everyone on the Net seems to recommend 5W 30!

Is this going to cause any harm? Do I need to do another oil change?

Thanks

[derekpara]

The ford M2C-913B spec replaced the original M2C-913A spec and is for both Ford petrol and diesels (with a few exceptions such as the new ford focus RS and the VW engined diesel fords. Oh and some of the new euro iv spec diesels).

Ford dont recommend semi or full synthetic, just a spec such as the Ford M2C-913B spec, and a viscosity 5w-30. For warranty purposes as long as the oil meets this spec what it is made from (semi or full) is down to the owner.

If you look here you will see a mix of semi and full synthetic 5w-30's that all meet the ford spec http://www.opieoils....-m2c-913-b.aspx

Cheers

D

[SlackAlice]

I doubt any harm will be caused to the engine by using a 5W 40 oil instead of 5W 30. The engine is 7yrs old (assuming it's the original) and is unlikely to be under warranty. How many miles on this engine?

[Richie616]

The car has 52000 miles and I have a warranty with Warranty Direct.

[SlackAlice]

If your under Warranty that changes the situation, inasmuch as you haven't used the correct grade oil.

Did you do the oil change yourself? Thought you had to use an approved garage to keep the Warranty valid.

[Richie616]

Yes but this in an 'unrequired' mid term interim oil change only. The car will still be getting the requisite annual service by the garage