New start up rattle in cold weather!!

[Russell]

The following is an observation. Not necessarly a problem.

I run Mobil 1 0w40 and have for about 15,000 miles and about three oil/filter changes. Until just this week, I thought all start up "rattles" had been eliminated. Belts and pulleys had been replaced as well as timing chain tensioner.

However, I have noticed on the first cold start of each day, temperature from 7 to 15 degrees, there is a rattle from front/top of the engine that seems to last until the engine partially warms up. It was gone until this week when we started to recieve much colder temperatures

I was told by some mechanic on another forum that if I get a "rattling Vanos unit" with Mobil 1 0w40 I should go to a heavier oil. I think he mentioned 15w50. However, he did not like synthetic oil.

Even so, I plan to change my oil/filter to Mobil 1 0w40 again in a couple of weeks. I will have about 4,000 miles on the current oil. I may also have an oil analysis done by Blackstone.

It just seems that the M50 engine must just rattle a bit as they get older.

Just my 2 cents

[Russell]

My wife's Ford Explorer Eddie bauer makes a belt related squealing noise when the temperature gets below 10 degrees. Belt and pulleys were replaced this summer on the Explorer.

Perhaps I am worrying a bit too much about my BMW. Or is there such a thing as worrying too much

The following is an observation. Not necessarly a problem.

I run Mobil 1 0w40 and have for about 15,000 miles and about three oil/filter changes. Until just this week, I thought all start up "rattles" had been eliminated. Belts and pulleys had been replaced as well as timing chain tensioner.

However, I have noticed on the first cold start of each day, temperature from 7 to 15 degrees, there is a rattle from front/top of the engine that seems to last until the engine partially warms up. It was gone until this week when we started to recieve much colder temperatures

I was told by some mechanic on another forum that if I get a "rattling Vanos unit" with Mobil 1 0w40 I should go to a heavier oil. I think he mentioned 15w50. However, he did not like synthetic oil.

Even so, I plan to change my oil/filter to Mobil 1 0w40 again in a couple of weeks. I will have about 4,000 miles on the current oil. I may also have an oil analysis done by Blackstone.

It just seems that the M50 engine must just rattle a bit as they get older.

Just my 2 cents

[632 Regal]

usually cold start rattles are because of slow oil pumping or a weak oil pump or bad check valve. This usually will happen with dino oil or too thick of an oil. Your oil filter drainback check valve might be bad allowing oil to drain back into the pan where your engine has to pump up the filter and push air through the system until you get oil pressure.

[Robin-535im]

If it's a cold-related problem, I would stick with the lighter weight oil. I'm thinking that if it's because oil isn't getting somewhere because it's flowing too slowly, the last thing you would want would be heavier oil!

Other than that.... Happy holidays is all I can say!