cheap Oils worth the punt?

[snowdmc]

Hi All,

Had a question about using unbranded (morrisions) 20w50 oil as a top up when the level drops slightly, through leaks or being burned off etc.

Now as the car is serviced regularly anyway, and the 20w50 is a mineral oil, which doesnt meet the same specs as the semi synthetic oils. Is it ok to use?

At about ?0.80p a litre on ebay, its way cheaper than the 'classic' brands.

Some people say, that branded is best, but i ran all my old cars on asda price 10w40 for years as it was ?4.50 a gallon with no problems.

Anyway i just wanted to get some opinions, especially as 20w50 is relatively hard to get hold of at short notice (was in halfrauds yesterday and they didnt have any). Yes it doesnt have the lubricating quality of magnatec etc, but it didnt in the 70's either!

[Heuer]

Jaguar specified changing the oil/filter every 2,500 miles so if you intend to follow that advice there seems little point in filling up with expensive oils designed for modern cars where oil changes can be anywhere from 50,000 to 100,000 miles. Go with the cheapest and change it at the Jaguar specified intervals. Remember that many owners only do around 500 miles a year in their cars so that would be a change every 5 years.

[snowdmc]

Thanks for the info, although I'm intending to do about 7500 a year all being well, I did 500 at the weekend already, may be worth signing up for that nectar card after all! obviously I'll need thrice yearly servicing with that kind of mileage.

[christopher storey]

I buy my oils 25 litres at a time . I do not use any synthetic oil, as generally speaking they are too thin for an engine designed over 60 years ago . I usually use an API spec oil either 15w/40 or if I can get it 20w/50 , from one or other of the large factors which guarantees a reasonable performance even if the modest additive quality means that they will not give full protection for as long as the most expensive oils. As David says , a relatively frequent change will give you all the protection you need

[snowdmc]

i spent a bit of time digging into this and found some interesting results regarding the API rating. see here for ratings http://www.unitedoil.com.au/apiclass.htm

The cheapo morrisons stuff is api SA - which has no perfomance measurement and is a base oil (byproduct) does not meet any performance indicators only its SAE rating.

From here it goes backwards through the alphabet, looks like the best of the full mineral oils is on rating SE.

And the standard semi synthetic 20w50 is up to SL rating.

I think i'm going to steer clear of the SA stuff, and put in SE as a minimum, however my mech has said they only ever use SL quality oils.

Following on from this i checked with Comma - being the 3rd biggest oil producer in the UK, their classic oil is SE rating and their premium (sonic) 20w50 is SL both of which they say are suitable for classic cars. about ?15 for 5L - going to give this a try.

I would suggest sticking with a higher API rated oil, rather than just regular changes, especially as the SA grade is known to promote sludge and separates under temperature. Hope that helps in some way.

[christopher storey]

That is very useful information. The ones I use are , from recollection, SG grade

[SESH]

I use Valvoline VR1 Racing Oil. It's 20W-50 and is SL rated. I normally buy it on a deal from Eurocarparts when they are doing a 25% discount. Comes out at around ?22.50 for 5 litres delivered free. It was recommended to me by JD Classics.
Mike