M54 higher mileage oil spec change. yay/nay?

C

Chris_D

Elite
 Mostly Holland. Sometimes UK.
Nathan released a couple of videos recently extolling the virtues of changing up to a higher weight oil on higher mileage M54 engines, based on higher oil consumptions. Spec is 5w30 (which I use) and Nathan suggests moving to 10w40.

I replaced my CCV system a few years ago and this cured the high oil consumption of my engine.
At 140k now and noticing that oil consumption is steadily creeping back up with topups of 5w30 needed every 1000 miles or so. Motor is fine with no issues and change my oil every 7.5k.

Thinking of 'transitioning' the oil spec at next service with a 50/50 mix of 5w30 and 10w40 using same brand (Castrol Edge Titanium LL04) with 50/50 top-ups until all 5w30 is used up or next oil service due.

Anyone NOT on 5w30 and has changed weight on high mileage M54 engines?

https://www.youtube.com/watch?v=K5jXFZbAD9o

snapshot.jpg
 
Would it not be better for the engine to just top up every 1000 miles or so with the thinner oil?

If you change the oil at 7500 miles its not going to break the bank.
 
MKZ4000 said:
Would it not be better for the engine to just top up every 1000 miles or so with the thinner oil?

If you change the oil at 7500 miles its not going to break the bank.
Click to expand...

I'm assuming he is looking at an overall, or long-term outlook on preserving the engine in the best way possible.
As factory tolerances / clearances go south due to higher mileages that it makes sense to move to a higher viscosity oil etc. and not just to cure any leaks. I ran an M52TU engine for almost 20 years and 258k miles on 10w40 and compression was still factory spec until someone t-boned it, so I'm inclined to agree with him. Not much to lose in trying I think.
 
My Z4 M54 3.0 did like to burn oil when I got it - I found moving to 5w40 helped significantly.
 
Assuming your doing this, I would be interested knowing whether the above changes your oil consumption? 50:50?
I guess try it for 1 or 2 thousand miles? Can quickly revert back to 5w30 if you need to...

This is provided your consumption every 1000miles is consistent? When I was driving mine lots, I think every 2 or 3 thousand I had to top up 500ml? Assuming you've got a fairly accurate idea of consumption per 1000miles?
 
kis said:
Assuming your doing this, I would be interested knowing whether the above changes your oil consumption? 50:50?
I guess try it for 1 or 2 thousand miles? Can quickly revert back to 5w30 if you need to...

This is provided your consumption every 1000miles is consistent? When I was driving mine lots, I think every 2 or 3 thousand I had to top up 500ml? Assuming you've got a fairly accurate idea of consumption per 1000miles?
Click to expand...

Well, put it this way; I'm buying 10L oil from my oil guy every 7.5k miles. I find when I get to the next oil service (7.5k) that I have used up most of the remainder after dropping in 6.5L at each oil service.

What's weird is that I always seem to suck out almost 8L of oil at each 7.5k miles service interval even when checking the level every week. I made a post on it a while back.
I keep the oil level at the upper end of the dipstick mark just be on the safe side. Hence, that 'block' on the dipstick probably represents a range of 1L.

That's not drastic by any means and certainly not as bad as it was before I swapped in the new CCV system.
I'll try to remember to update this post. 3.5k to next interim oil service....
 
I used to put Shell Helix Ultra 5W/40 to LL01 spec in my 325ti with an M54engine - mainly because I could get it at Tesco when it was on special offer - and it didn't seem to do it any harm!

I couldn't see how having a wider temperature range would cause a problem, but what you are proposing is slightly different. Couldn't you get 5W/40?
 
There's absolutely no problem with running any LL04 (or LL01 for petrol BMW motors) spec 5w40.

I found that when running 5w40, my N55 135i, my N52 130i and my brother's M54 engined X3 all ran a tad quieter and the N55 and M54 used less oil.

These engines all run fairly warm, so I always prefer to use a slightly higher viscosity (hot) rated oil. If it's LL04 spec, it's BMW approved...
 
You must log in or register to reply here.
Back
Top Bottom