what oil to use?

[SHAKEELE30]

wanted to ask what oil to use for a 325???

[Prey]

From reading about on here it looks like 5w30 is oem, 10w40 is also fine though.

[e30-EVN]

I always used 10-40 part synthetic in mine mate

[TouringTash]

10W-40 part synth and replace oem filter and oil every 6000 miles. No need to go mental on super expensive stuff either.

[Morat]

I go by the service lights, which still seems to work out at about 6k miles. It must be my short commute...
Is 5/30 really the original grade? I thought that spec was a more modern one.
10/40 semi for me too.

[capri_rob]

Using Comma 10/40 Semi Synthetic in mine but in truth its a bit too thin when the engine is up to temp.

When these turds were new 20/50 was the norm and I'm probably gonna give a good quality one a go next time to try and quieten it down a bit more.

[rp2]

if you search on any proper oil website such as castrol or opie oils it lists the rating for the 325 m20 engine is 5W40. it says this in the owners handbook too!

i would buy 5W40 as this is what the engine is designed for, or maybe 5w30 if 5w40 isnt availiable for some reason, definatly do not use 20w50!

[Prey]

Mine will be getting a decent quality 10w40 semi but I'm sure the service history lists either castrol or mobil 5w30 for a lot of it - I can't remember though, I'll check!

20w50 would seem a bit industrial, I have this discussion with a mate of mine, he says that the tolerances wear in the engine (which is fair enough) but I reason that the oilways and feeds etc don't wear, if anything they may block up as time goes on, so you wouldn't want to go running anything too thick for risk of starving oil in the wrong places?

[Brianmoooore]

the rating for the 325 m20 engine is 5W40. it says this in the owners handbook too!

i would buy 5W40 as this is what the engine is designed for, or maybe 5w30 if 5w40 isnt availiable for some reason, definatly do not use 20w50!

You must have a different handbook to me!
My handbook lists 20W-50 and 15W-50 as the most suitable oil for the range of temperatures experienced in the UK, and 5W-30 only suitable for temperatures below -5 degrees.
Having said that, the handbook was written 25 years ago, for 25 year old oil technology, and the current recommendation seems to be for a 10W-40 semi or full synthetic, or something close to that.

[AlpineAde]

My handbook lists 20W-50 and 15W-50 as the most suitable oil for the range of temperatures experienced in the UK, and 5W-30 only suitable for temperatures below -5 degrees.

That's what mine says too.

I very happily use premium 20w-50 oil in our Australian climate. And even 20w-60 on track. 10w to 20w-40 to 50 is the oil range used by every E30 owner I have ever met here.

A 10w-40 would be pretty much spot on for you lot.

[Morat]

Hmmm, you can get 10/50 oil nowadays. I wonder if that would give more protection when hot than 10/40?
I do a lot of cold starts so I'd like to keep the better protection afforded by a 10w oil.

[maxfield]

I use 10/40w Semi. Engine seems to run fine on that.

[rp2]

You must have a different handbook to me!
My handbook lists 20W-50 and 15W-50 as the most suitable oil for the range of temperatures experienced in the UK, and 5W-30 only suitable for temperatures below -5 degrees.

yeah i seemed to imagne that? i was sure i read that in my handbook! but i just checked and im wrong.

but it does reccommend 5w40 on every site ive checked. and even halfords

[Kos]

Hmmm, you can get 10/50 oil nowadays. I wonder if that would give more protection when hot than 10/40?
I do a lot of cold starts so I'd like to keep the better protection afforded by a 10w oil.

on a cold start there is no difference between a 10w50 and 10w40.

if you plan on doing track work in the summer time when temps will be higher a 10w50 would be better.

in the winter i use a 5w40 and summer 10w50

for a road car, 5w40 and synthetic is all you'll ever need

[Morat]

Well that's my point
When the handbook was published they listed 20/50 but you probably couldn't get 10/50.

At the other end of the scale I'm not sure how much difference the weather makes to the running temp of the engine once it is warm. I can see that track work would put the temps up, but does 10-20degrees difference to ambient really make the engine run much hotter?

[pony]

I USE MOBIL 1 FULL SYTHETIC OIL. It is good enough for McLaren then it is good enough for me!! I use 0W-40.

http://www.mobil-1.co.uk/cms/new-life-0w-40.aspx

PS the Castrol website recommend Castrol Edge Sport.

[SHAKEELE30]

so i take it 15/40 is the wrong one

wasnt too sure so i end up getting this one, but havent used it yet...

[Kos]

it will work and do a job. not ideal no its getting quite cold