Engines for BMW <span title="!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!?">!!!!!!!!!!!!!!!!!!!!!!!!!...</span>

Question

What type of engine oil for BMW 525i 1989 with 143000 miles?

Answer 1

Ahh, the age old oil question. There has always been a debate about this, and there may not be one right answer since we all have a preference. There is some degree of opinion in this answer, since it is based on my own experience.

The best stuff I&#039;ve seen in all the reviews of oil specifications/ technical literature is the Mobil-1 full synthetic oil. This is what I&#039;ve been using for many many years, without any problems, and my current BMW has over 150K miles on her now. The reason for a full synthetic over &quot;dino&quot; or raw crude oil is there are more additives that benefit your engine, and you can have a longer service interval on synthetic than you can on natural oil. You can run synthetic for 5-8K miles (though I don&#039;t recommend it), while natural oil needs to be changed about every 3-5K miles. I change mine every 3-5K, despite what a shop puts on the sticky tag in your windshield. [of note, if you have a turbo engine, I recommend natural oil, as you can build more pressure, and it gives back more power to the turbo].

For this engine I&#039;d go with the extended mileage version - I think it is in a red cap version. There are special additives in it that help to soften up old seals and keep them plump so they don&#039;t crack. They also help to seal up micro scratches in the cylinder walls so the pistons seal better, boosting compression. This will increase gas mileage.

On the down side, it contains detergents, which are good, but with a caveat. Many people will want to get old sludgy oil out of their engines (which is a good thing), but if that sludge is blocking a leak, the detergents will wash away the sludge and your engine could start to leak oil somewhere. Therefore, some people blame the oil for CAUSING leaks, when in fact they were already there.

For a 525, I would recommend a 10W30 oil or a 10W40. This acts like 10 weight when it is cold, but no more than 40 weight when it gets hot. To understand more about engine oil weights, do a google search. But if you had a more performance oriented engine like an M5, I would recommend 15W50. In the winter, as it gets colder, I would recommend something like a 5W30 or a 0W30 depending on how cold it gets.

The best place to find it is at Walmart (unbelievably) for about $22 for a 5 quart jug. This is cheaper than any shop will sell it to you for. Not all Walmart stores will have it, but most do.  

Answer 2

I use full synthetic for my 2000 M5. As for oil weight, check with a BMW dealer for correct type, they can tell you better than anyone else. Just give them a call and they could help you out.

Answer 3

Castrol 20/50