6 replies to this topic

[rpowell86]

Year:1988 City E
Description of problem (please be as in depth as possible):
Hey, Im going to be changing the oil in my manual 998cc and dont know whether I want the 20w50 or the 10w40

Can someone tell me the correct oil for this car, or a general rule of thumb?

Also why do I need mineral and not synthetic?

Thanks,
Ryan

Any non-standard parts that might be involved with the problem?
Stage 1 kit

[Retro_10s]

Mini engines were designed to run on Mineral Oil and as such should only be run on Mineral. Don't forget you're driving about in a car that had the same basic design throughout it's entire production life. It's a 50 year old design and it's fairly unique these days due to the engine and gearbox sharing the same oil.... and this is Almost the full reason that synthetic is not recommended, it's down to the gearbox and the Diff - Put simply - With all the oil being shared, the mini gives it a tough old time in there being thrashed about - Synthetic simply can't cope with lubricating the Gearbox/Diff and engine - it's simply too harsh an enviroment for the oil to cope with. When asked regarding this - Mobil agreed.

The oil you should run is 20w50 Mineral - this is available from Halfords, Motorfactors and most other good Car supplies stores. Make sure you buy a good brand such as 'Halfords classic oil', Duckhams, Millers, Penrite, Castrol, Comma, Valvoline make a very good 20w50 too - they all do their own version of 20w50.

Most of these oils contain detergents and additives that are kind and helpful to older engines - things such as seal swell to help any leaks you're experiencing and to keep the internals clean and free from deposits - There's also a theory floating about that Mineral based oils are better at cleaning out swarf from things like synchros etc..

Please do a search for 'Which oil' threads already on the forum - it's been asked millions of times - twice this week already in fact. Thanks.

[james962]

Good post retro

[Big_Adam]

I'd like to add this suggestion - Buy two bottles of oil.

Most containers now seem to be 4.5l, guess how much a mini needs?

5liter.

It also means you have plenty to top up with. I use the system of "as soon as second bottle is empty, oil change time" seems to work well.

[Fire_monkey]

halfords do a good 20W50 in 5 liter for 15 quid

Edited by Fire_monkey, 11 July 2009 - 03:11 PM.

[Teapot]

Thanks, Retro_10s. You're a patient man. That's the best concise summary of a mini's oiletry needs I've seen, and I've saved it to my tmf file of wisdom, currently running at 4 megs of notes. Course, I can never find the bit I want ....

[jaydee]

This question has been asked about 4 times during this week, I think its time to put one of these topic pinned here, as nobody is going to look in the FAQ section and the search function isnt really good.