0W-20 in a BMW?

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quote:

If I wanted to get the ultimate gas mileage from my econobox 1.8L BMW, would it be advisable to use a 0W-20 oil like M1?

Not if you want your rod bearings and cams to be happy.
wink.gif
Get an A3 rated oil.
 
As was mentioned, it's probably safe to use this grade in extreme cold, but from experience in my 1994 DO NOT use this water-like grade in the summer. The most likely explanation I can come up with is that extreme heat will cook the oil in the engine and you will shorten engine life considerably. German cars are designed to last a very long time. However high speed, high rpm, 10k mi. intervals and water-like oil grades do not mix....trust me, the fuel economy or HP difference is not worth much. Use an A3 oil.
 
(sorry got cut off)

using this grade in temps over 30F, you will most likely get gradual increased consumption followed by carbon deposits on the rings, valve seals and stems, followed by sticking of the lifters, and accelerated wear of the pistons/walls, etc. which will DECREASE HP and acceleration. So is it really worth it? The process will begin immediately, but take about 60-100k to become noticeable with respect to the butt-meter...
 
quote:

Originally posted by Dr. T:
(sorry got cut off)

using this grade in temps over 30F, you will most likely get gradual increased consumption followed by carbon deposits on the rings, valve seals and stems, followed by sticking of the lifters, and accelerated wear of the pistons/walls, etc. which will DECREASE HP and acceleration. So is it really worth it? The process will begin immediately, but take about 60-100k to become noticeable with respect to the butt-meter...


I still don't understand your logic here. Why is it that you seem to think a thin oil is going to leave the engine more dirty than a thick oil would? And if anything, a good 5w20 or 0w20 should keep things even cleaner since chances are very good that it has little to no VII in it.

Same with a good 0w30, 5w30 or 10w30 synthetic, they'll have very little VII in it too, so how is it that you figure it'll end up keeping things dirty compared to something like 5w50 Syntec, which I know you like a lot but yet we all know that oil is LOADED with VII and would most likely dirty up the engine much more than Syntec's thinner oils would.

As much as I'm not one of Mobil 1's biggest fans, I will say this: I've seen a lot of pictures of people's engines who have torn them down (putting in aftermarket cams for instance) and the insides look extremely clean after running nothing but Mobil 1 5w30 or 10w30, some even with well over 100,000 miles on them too.

I'm sure our Amsoil reps on here could tell us about some of their long time customers who use nothing but 0w30 or 5w30, and have very high mileage clean engines too.

It's not the viscosity of the oil which causes an engine to get dirty, it's the quality of the oil. Sure, a 5w30 dino is most likely to have more VII than a 20w50 dino, so in that case the thinner oil would sludge up easier. But when you're talking about a high quality 0w30 or 5w30 synthetic, I don't think you'd see either of those get your engine dirty unless you severely push the intervals too far, or have some sort of mechanical problem.
 
Patman, it's called burn-off. VI's shearing and floating around are less of a concern to me than using an oil that will ultimately burn off along with it's encompassing VI's because one is using an oil that doesn't have the balls to take the heat.

It's like this. All oils have VI's. All oils will shear. All oils will thin out as they shear and then thicken as they become contaminated. However, if you start off with water-thin oils, you will get burn off and ensuing consumption. Where does the burnt oil go? Out the tailpipe? All of it? Take a 0-20 and then take a 15-50 and put them in a frying pan. Both will turn the pan black. However, the 0-20 will turn black much sooner at a much lower temperature. The black part...this is what's coating the engine. The 15-50 remains fluid. Where are the VI's in the 0-20 to help it out? They're burnt. In the 15-50, they're harmlessly floating around. As you can see, the 0-20 will degrade from day one, begin to leave deposits and end up costing power. There's 3 ways around it and that's why 5-30's work in N.A.. One, keep using auto-rx. Two, change oil every 3k. Three, change car because engine's worn out at 100k.. This is why N.A. has $.99 oils and they work just fine...or do they?

I've used both M-1 5-30 and BMW 5-30 oils in German engines and both left visible sludge behind most likely from volatility burn-off due to being an inferior viscosity for the job. Synthetic or otherwise, the 30 weight in these engines is not up to the task in the long haul. So, I dread to see how long a 20 weight will hold up past the warranty period.
 
quote:

So, I dread to see how long a 20 weight will hold up past the warranty period...

EXACTLY! There is no long-term data to base any wear assumptions on using xW20. Every single Ford and Honda owner using xW20 is a long-term experiment in progress...

Good luck to you all...!
 
quote:

Originally posted by Dr. T:
As was mentioned, it's probably safe to use this grade in extreme cold, but from experience in my 1994 DO NOT use this water-like grade in the summer. The most likely explanation I can come up with is that extreme heat will cook the oil in the engine and you will shorten engine life considerably. German cars are designed to last a very long time. However high speed, high rpm, 10k mi. intervals and water-like oil grades do not mix....trust me, the fuel economy or HP difference is not worth much. Use an A3 oil.

Dr T,
I think you are missing the point......there is no "high speed", "high RPM" operation here.....it's an econobox 1.8L engine......probably the daily beater to go to work and back. I still maintain that I wouldn't be a problem at all and would be worth a try in a 3k mile OCI.
Rick

EDIT: Not to mention many 20 weight are .1 shy of being a 30 weight. Heck, you run Chevron 5W-30 and by 3k miles you already have a 20 weight.

[ January 05, 2004, 08:07 PM: Message edited by: Last_Z ]
 
quote:

Originally posted by Dr. T:
Patman, it's called burn-off. VI's shearing and floating around are less of a concern to me than using an oil that will ultimately burn off along with it's encompassing VI's because one is using an oil that doesn't have the balls to take the heat.


You are missing the point again Sir. There isn't much "burn off" if at all with a quality 20 wieght....as Patman stated, they don't contain a lot of VIIs. Castrol 5W-50 on the other hand, must be loaded with it.
You must think that because an oil is thinner, it is more gasoline like and would evaporate quicker or something. I don't think that's true or else the various vehicles running this weight would be bone ry by 3k miles.

BTW, I'm a thick oil lover.....your argument doesn't make much sense to me though........no offense.

[ January 05, 2004, 08:19 PM: Message edited by: Last_Z ]
 
quote:

Originally posted by Dr. T:

It's like this. All oils have VI's. All oils will shear. All oils will thin out as they shear and then thicken as they become contaminated. However, if you start off with water-thin oils, you will get burn off and ensuing consumption. Where does the burnt oil go? Out the tailpipe? All of it?


I still don't understand your argument. My next door neighbor has almost 400,000km on his Sunbird, and has used nothing but 5w30 synthetic since new. It doesn't burn any oil. My wife's car is almost at 80,000km now, using nothing but 5w30 so far (and 0w30 right now) and her engine uses no oil between oil changes. There are many people on here who have used nothing but 5w30 or 10w30 since new and have no oil consumption issues, even with higher mileage. So if these people are getting no consumption, how is it they are going to end up with any problems?

Perhaps if someone runs 5w30 in a German engine which is designed more for a 40 or 50wt oil I could see a problem, but for 95% of the cars on the road, a good 30wt oil is the way to go. Terry Dyson has told us this many times, are you doubting his many years of experience?
 
I have seen some good improvements in mileage by switching amongst different brands and grades of gasoline. You may get improvement in finding a gas your bimmer "likes". I'm not kidding, all fuels don't give the same mileage results!

I think a 20 wt. is just asking for trouble. The HT/HS just wouldn't be up to snuff imho.
 
Patman wrote:
>Perhaps if someone runs 5w30 in a German engine which is designed more for a 40 or 50wt oil I could see a problem, but for 95% of the cars on the road, a good 30wt oil is the way to go.
Exactly! My 1993 Pathfinder ran either M1 or BMW 5W-30 and used less than 1/2 qt. between 7500 mile oil changes. My Jeep TJ 4.0 uses no M1 10W-30 between 6000 mile changes. In both cases I used the oil viscosity specified by the manufacturer. When I switched my M42 from M1 15W-50 to BMW Synthetic 5W-30 my oil consumption increased from 1 qt. every 3600 miles to 1 qt. every 2600 miles. The M52 in my 1997 528i used no oil between @8800 mile changes when running M1 15W-50 or Rotella T Syn 5W-40. It has consumed @1/3 qt. of BMW 5W-30 in 5800 miles. In both cases the engines' viscosity charts allow 15W-X oils to be used down to 0F, while the use of 5W-30 oils are only recommended for ambient temperatures of 24F and below in the case of the M42, and 50F and below in the case of the M52. While the jury is still out on the continued use of 5W-30 in the 528i, I plan to continue running M1 15W-50 in the 318ti. Since the engine often operates for over an hour at 4000 rpm or more-in ambient temperatures of >90F-I simply don't feel comfortable running an oil that the manufacturer only considers appropriate for ambient temps some 65 degrees lower.
 
Hi,
the Owners's Manual for my MY98 Z3 2.8 lists the same oil requirements over four engine types 1.8, 1.9, 2.8, and M

These are A2/A3-96,B2/B3-96 and the following viscosities:

5w-20 @ -30C to 0C
5w-30 @ -30C to 10C
10w-30 @ -20C to 10C
10w-40 @ -20C to 20C
15w-40 @ -15C to 30C>
Special Oils ( synthetics )
0w-X & 5w-X @ -30C to 30C>
10w-X @ -20C to 30C>

As mentioned earlier I use Del 1 5w-40. Ambient temps here are from 0C to 45C so it is an excellent all year oil for me - it is 35C today!

Considering my own experience with GC SLX 0w-30 and M1 10w-30 in Bimmers I think you would be best on Del 1 or similar. SS M1 10w-30 should be OK too but any lighter viscosities are not a great idea in BMW engines especially the Vanos models due to actuation issues

Regards
 
Well, there you go then...

We are talking about BMW here...that was the original post hence, other cars manuf. aren't pertinent.

Second, the car in ques. is a 1.8L 4 banger...yes, it revs higher and needs more rpm's to reach a certain speed/hp potential. The higher the speed (rpm) and the thinner the oil, the greater propensity of both blow-by and consumption. What's not to see? Bob posted this observation going 85-90 mph in his Escort for prolonged periods. MCompact mentions it due to using a thinner grade. Driving faster and/or using a thinner grade can increase consumption.

Lastly, I know it's not Germany and I don't know how you wusses drive, but driving home yesterday I hit 110 mph (cruising at about 90 mph for ~1hr) in 28F dry weather. About 4k rpm. Do you think a 0-20 would provide the same protection?
 
quote:

Originally posted by Dr. T:
Well, there you go then...

We are talking about BMW here...that was the original post hence, other cars manuf. aren't pertinent.


But you always tell people no matter what car they drive, that a 30wt oil is too thin for them, you don't only mention this when German cars are being discussed. That's my point, even though I used this thread about BMWs to air my views on your thoughts.
 
True I'm guilty of that. That's because I hate seeing consumption. I've had consumption with 5-30 in every car I've owned or had experience with...from 1.6L Honda's to 2.3L Fords to 4.6 DOHC V-8's to 6.0 V-12's. New or old.

So I'll re-iterate A3 rated 30 weight should be a minimum standard for any engine (unless longevity is not desired). Moving up in grade concurrent with consumption.
 
quote:

Originally posted by Dr. T:
True I'm guilty of that. That's because I hate seeing consumption. I've had consumption with 5-30 in every car I've owned or had experience with...from 1.6L Honda's to 2.3L Fords to 4.6 DOHC V-8's to 6.0 V-12's. New or old.


So then would you agree with my assertion that if you aren't seeing any consumption with a 5w30 or 0w30 oil, and your UOAs are showing good numbers too, then there is no reason to go with a thicker oil?
 
I do not want to be drawn into this one.

All I have to say is my new car had 200K miles and ran like new when I traded it.

It's still going. 1989, 3.3L GM V-6

Castrol GTX 5-30, never used a drop.
 
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