What’s the best engine oil on a m20 325i,10w40 semi 5W-40s

[Pritesh]

What the best engine oil on a m20 325i
Getting mixed messages between 10w40 semi synthetic and 5W-40 full synthetic
Car only does 500 miles a year
Also how often does the gearbox oil and lsd oil need to be changed?

Thanks all

[Mitchen]

10w40 magnetec for the engine.

Gbox and LSD every insp 2.

[darkchild]

10w/40 Magnatec is perfectly adequate. Even the cheapest oils will likely be of a higher spec than when these cars were new.

However...

5w/40 full synthetic is far better and the default choice if you're happy to spend a little extra.

[martauto]

Even the cheapest oils will likely be of a higher spec than when these cars were new.

Check out the supermarkets and the spec for their own brands and like has been said, they will be better than the stuff 30 years ago.

Mart.

[TurtleDesignTech]

Mobil 1 fully synthetic 0w40 from Amazon, £37 delivered.



The Mobil 1 range of oils are some of the best on the market in Europe at a reasonable-ish price.

This guy independently tests oils independently and has complied an exhaustive list: https://540ratblog.wordpress.com/2013/0 ... t-ranking/

As you can see, the Mobil 1 oil recommended came 5th.

Bottom line is though: use fully synthetic oil and change it regularly.

[BenHar]

Mobil 1 fully synthetic 0w40 from Amazon, £37 delivered.



The Mobil 1 range of oils are some of the best on the market in Europe at a reasonable-ish price.

This guy independently tests oils independently and has complied an exhaustive list: https://540ratblog.wordpress.com/2013/0 ... t-ranking/

As you can see, the Mobil 1 oil recommended came 5th.

Bottom line is though: use fully synthetic oil and change it regularly.

Or waste your money on the oil that the manufacturer recommended.

Ben

[Simon13]

don't use 0W-40 its like piss

[TurtleDesignTech]

don't use 0W-40 its like pee pee

The 0w is only the winter rating. Therefore, it keeps a viscosity correlating to the 40, all the way down that 0w winter rating temperature.

It is no difference in viscosity in most normal operating ranges, except for when it is very cold, when it remains more fluid than something that is 15w or 30w rated. i.e. it flows around the engine better.

There is no harm in having a oil that is rated for more extreme winter temperatures.

The E30 wiki even recommends anything with a winter rating of 0, 5 or 10. - http://www.e30zone.net/e30zonewiki/index.php/Oil

[reggid]

I've use 10W-40 last couple years before than 10W-50 but its a bit thick if the oil isn't getting super hot

the difference between 0W-40 and 10W-40 from 0C up is pretty negligible. below -5C the difference become more pronounced the colder you get

[arrisbmw]

its more important to change the oil than the numbers. it depends where you live climate etc, but any 10-40 is fine.
more vital to the engine life , not to boot it until engine is warm, our modern day multi grade oils are brilliant and that's why the engine last so long. Saying that the e30 engines o.m have a spray bar arrangement for top end lub. which means the cam is last to receive itsoil.