What oil (not brand)

[CarsSuck]

Im currently using a 15w50 Mobil1 syn. It seems to be a bit heavy in the cold (early mornings below freezing, not uncommon to see the teens). What do you guys run in the winter and what do you run in the summer? I was thinking a 10w40 would be better, but im a tad worried about developing small leaks.

[Brew]

10w40 is just fine for your motor. Definitely get that 15w50 out of there before the temps start to drop below the 30s at night.

[CarsSuck]

HAHA waaayy too late for that.

[Mystikal]

5W-50 Castrol Syntec.

Incredible stuff, no sacrifices. That said, I still switch to 15W-50 Mobil for summer.

[mark1]

0-40 M1

[Axxe]

0-40? Where do you live, siberia? That's one of the first oils to break down, it's got such a huge spread.

[DaN]

I was looking at the e30 owners manual, it said 15w-50 is useable down to about 0 degrees F. I currently have Mobil 1 15w-50 in my 325i. I don't think I'll change it. I just let it circulate a minute before driving.

The synthetic stuff flows nicely at low temps.

[CarsSuck]

Well when its down in the teens i can tell at start up that the oil is thicker than sin because it turns over slowly and doesnt want to rev until it warms up. just to make sure im thinking correctly, the first number is the warm viscosity and the second is cold, right?

[hamann318is]

I use 15w50 most of the time. The local BMW shop told me that's all they run in the M42. I ran 10w40, and I was getting some very small leaks.

[DaN]

The first number is the viscosity at colder temps, w- winter. Second is operating temp.
I doubt the oil is slowing your crank speed.

[mrsleeve]

The first number is the viscosity at colder temps, w- winter. Second is operating temp.
I doubt the oil is slowing your crank speed.

I bet it is on verry cold morrings.

[DaN]

nah

[Mystikal]

I was looking at the e30 owners manual, it said 15w-50 is useable down to about 0 degrees F. I currently have Mobil 1 15w-50 in my 325i. I don't think I'll change it. I just let it circulate a minute before driving.

The synthetic stuff flows nicely at low temps.

I still had my 15W-50 in as the temps went down to 40-50, and the entire week after I changed to 5W-50 I couldn't believe how different the car behaved when cold.

15W-50 is too much for our climate man, get it outta there.

[DriftinE30]

5W-50 Castrol Syntec.

Incredible stuff, no sacrifices. That said, I still switch to 15W-50 Mobil for summer.

I 2nd that.

[318i1985]

I'm running 15w40 Royal Purple with no complaints