Any - Does it really matter what oil I use to top up

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Wed 3 Nov 2021 18:54
Any - Does it really matter what oil I use to top up - Halmerend
….as long as it’s decent oil?

So I’ve done an oil check on all the main sites including Castrol, Europarts etc. and every one seems to recommend a different grade for each of our family cars!
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Wed 3 Nov 2021 18:59
Any - Does it really matter what oil I use to top up - craig-pd130

What cars do you have? Some oils from the likes of Castrol etc fulfil multiple manufacturers' requirements (e.g. BMW Longlife, Dexos 2 for Vauxhall, etc).

The owner's manual will give you a good idea.

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Wed 3 Nov 2021 19:05
Any - Does it really matter what oil I use to top up - Halmerend
The owners manual for my Audi says speak to the dealer, no oil specification at all in the manual as far as I can see. A five year old 1.0 A1 a newish petrol Q5 and a three year old 1.0 petrol Civic.
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Wed 3 Nov 2021 19:08
Any - Does it really matter what oil I use to top up - Halmerend
And I don’t get why the long life oil recommendation is 0w-20 yet the short life is 5w-40 for an Audi. It baffles me. Hence the question, does it really matter if I’m only topping up if needed?
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Wed 3 Nov 2021 19:21
Any - Does it really matter what oil I use to top up - elekie&a/c doctor
Fuchs 5-40 Titan synthetic seems to be correct for your Vw/Audi models . About £25 or less for 5 litres on flea bay . Can’t see you needing anything else .
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Thu 4 Nov 2021 00:40
Any - Does it really matter what oil I use to top up - edlithgow
And I don’t get why the long life oil recommendation is 0w-20 yet the short life is 5w-40 for an Audi. It baffles me. Hence the question, does it really matter if I’m only topping up if needed?

Perhaps they assume (state?) that the short life oil is for more severe service, so it gets changed more often, and benefits from the better protection of the higher viscosity.

Or (/and) the 5w-40 is cheaper, whereas the 0w-20 might be cost-prohibitive on a short OCI., Maybe the 5w-40 shears down more.

Lots of possible reasons. You are unlikely to get the full truth from an oil company marketing department and most people wouldn't want to.

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Thu 4 Nov 2021 09:16
Any - Does it really matter what oil I use to top up - RT

VW Group oil specifications often include several viscosity ratings - and VW dealers have moved down the numbers in recent years.

I'm surprised that any modern VW Group engine is using -40 viscosity in the UK.

My own 2016 VW Touareg TDi requires VW 507.00 for both long life and regular service regimes but gives a choice of 5w-30 or 0w-30 - I've chosen the latter albeit more expensive as it should protect better during cold starts and protect the same at hot temperatures.

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Fri 5 Nov 2021 18:16
Any - Does it really matter what oil I use to top up - Halmerend
Thanks. I’ve bought a litre of VW 0w-30 504.00 507.00 and will use that if any of them need topponung up.
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