Couple of E39 questions

[rusteee 52]

Hi there

My E39 (2002 530i M54B30 Msport) is due for a service again. Asking for a bit of advice on oil as a bit confused. Done a bit of research on oil viscosity and what to use with my car. Last time I had it done a Total 7900 I think 10w40 grade oil was used, multi deisil or petrol. I questioned it firstly because of the detergents, being both grade, and secondly as the manual specified 5w-X. The mechanic absolutely swears by this oil, and I havn't had any issues between service, as well as he's been using it in my old BMW over the 60,000kms I had it, and still using it. Will it be OK to use the same oil again? I know it is very good oil, just don't know about being in a BMW specd for 5w-X, or should the 5w-30 oil be used?

Also, I have a strange hassle where going UP the bombays the temperature gauge on my car starts to drop till it gets to about quarter. Gauge stays stationery, on half way all other times once up to temp, does not move at all. I just thought it was strange that it drops, when really if anything it should be increasing?? Has anyone come across this before?

Thankyou

[Allanw 1064]

The oil you use does depend on the frequency of changes to a certain extent. A lot of the things BMW specify are around the long life of the oil. Having said that, 6.5 litres of oil can stay in for a while before it gets as dirty as 4L would in the same conditons.

I thought the M54 had 0-w30, 0-w40, 5-w30 or 5-w40 specced by BMW??? Can't really recall now.

Regards to the grade, 5-W40 and 10-W40 will be about the same thickness when up to temp, and to be honest, the difference between the 10 and 5 when cold probably makes little difference.

If you are really pedantic about oil, you'll want oil that meets BMW's specs - LL01 AND ACEA A3/B4. Castrol Edge 0W-40 A3/B4 was at Repco when I did my oil, and it meets the grade very well. I'm going to run it to 15,000 instead of the 22,000 or so the service lights run to in our car. It's the ACEA A3/B4 that says it meets the viscosity, shear and temperature specifications from BMW.

Having said all that, there's plenty onf BMW's out there running the wrong oils, and they (mostly) don't seem to have major issues.

The temp gauge thing... have you made sure that you are full of coolant? If the level is low the sensor may come out of the liquid, and it may start to read low (unlikely though, as the cooleant temperature sensor for the gauge is quite low on the block). The M54 does adjust the thermostat electronically, but it opens is artificially, by heating the mechanical part of the thermostat. 1/4 on the gauge is getting down to about 60C, which is very low - normal is about 80 under load, but cruising can be well up into the 90's. Weird.

[NZ BMW 368]

The weight of your oil is to do with your climate and ambient temps.

I just use Mobil 1 and change it every 10,000km's or less. Yes, it's probably overkill but it's a tiny cost IMO and I personally regard it as the best oil. I'm aware some will disagree with that, but it's my car.

Edited September 25, 2012 by NZ BMW

[rusteee 52]

Brilliant! Thank you for the responses, appreciate it. I think I will use the 5W-30, as since last oil change (when this 15w40 grade was used) I get a couple second tappet noise when starting on very cold mornings, and from what you've said, it makes sense as to why unless its a pretty good coincidence.

I always live by the 10,000kms or every 6 months oil and filter. Which it usually ends up every 10,000kms as this cars all highway driving =D

Should the gearbox be done aswell? I know its lifetime seal etc but i'm always a bit iffy about that. It changes gears etc smooth and no hassles, but it has 230,000kms on it? Otherwise use it till it dies then change it I suppose.

[speedyg 16]

I have had both my 530i's auto boxes flushed and new fluid, some people are too scared to touch them. I haven't had any issues though (touch wood)