huhjared

Hi Guys,
I was just thinking about servicing the car soon and went to undo my oil filler cap.
What I saw next was just bad...
There are definitely some black sludge starting to build up in the engine.

I was wondering what would you guys do in my situation?

Would you use an engine flush to flush the engine?
Liqui-Moly Engine Detox or Liqui-Moly Engine Flush Plus?
I heard that engine oil flushes will do more harm to the engine?

Also with the engine oil, would you use Castrol edge sport 5w-30 or Castrol edge sport 0w-40?
Would you also use addictive like Liqui-Moly MOS2 ANTI-FRICTION in the new oil?

Thanks in advance for any advise.

2006 525i
N52 engine with 73000km on it.

huhjared

No suggestions?

turboawd

i dont like engine flushes, cause you are basically putting a solvent in your motor.

do you go a long time between oil changes? do you use synthetic?

if it were me, i would do an oil change(synthetic), drive it for 100 miles, and then change it again, then maybe change it once more after 1000 miles. then again at 3k, then every 5k.
oil sludge is not good, and frequent oil changes can help clear things up.

jrsamps

Are you sure it's sludge? Probably just some oil and dirt mixed in around the cap. How many miles on vehicle?

luigi524td

The advice on short mileage and time oil services are good. But, I feel the 100 / 1000 / 3000 miles are a bit overkill. I'd definitley do an oil and filter service but after a good long highway speed run. Deposits that look like sludge on the filler cap often indicate that the car is driven short trips and not up to operating temperatures for a sufficiently long time to eliminate ('cook off'') moisture and condensation that normally accumulates in the crankcase. As a safety measure you should have the cooling system investigated to ensure there are no internal leaks adding to the situation.

If you are not driving this car in long runs (100 mi+) at least once a month you should do oil changes more regularly (at least once a year).