Did I hurt something?

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Dec 26, 2002
Hi all, Newbie here. I did a search, but couldn't seem to find exactly the answer I was looking for. So I'll ask my question.

I drive a 2001 BMW 330i & used to live in LA.
I was running my car very hard in 100 degree heat at track events. I was using Castrol Syntec 5W-50, cause I felt the 5W-30 (which BMW recomends) was too thin.

I moved back to the Boston area and I have been using 5W-30 since I got here. I have changed my oil twice since I moved back (5000mile intervals) and twice now I have had to add oil between changes. After the first change I had to add a quart after about 2500 miles. The second time I had to add oil after 2000 miles and then again at 3300 miles.

My question is where is my oil going? Did I damage some kind of seal using the 5W-50 because it is thicker, and now the 5W-30 is just seeping out or blowing past the rings and getting burned?

I am coming up on another oil change and I'm not sure if I should continue using the 5W-30 or go back to 5W-50. Also, BMW recommends Castrol, but should I think about Mobil 1 or Redline?

Any ideas?

oh, and I used the Castrol Syntec 5W-50 cause I couldn't find the Syntec 5W-40.

Thanks All
Not sure about the oil going places.....but Mobil 1 , Redline and Amsoil are better oils then Castol. Read this:

However, don't just go by this article. Any of the brands above are all very close. Some say Mobil 1 is still the best oil,(now with Moly) while others are fans of Amsoil. It's kind of like a Ford vs Chevy, Joe Montana vs John Elway thing.

[ December 27, 2002, 01:38 PM: Message edited by: buster ]
Oil consumption will vary by oil and weight and driving conditions. If you were leaking it you would probably notice it somewhere so assume you are using some. BMW would not consider your usage abnormal and the real key is to see if it stabilizes or continues to increase. Many cars use a quart per 1-3000 miles since day one and never increase which is fine. As sugested above, try anther brand first of all and see what happens. The heavier weight in LA may be necessary in Boston, perhaps a 0W40 would work
Go with a bit thicker oil and see if it gets consumed too. BMW engines are weird too, they take longer than normal to completely break in.
Since my first post I have been searching and learing A LOT! Correct me if I'm wrong, but the first number (5W) is based on oil at cold startup right? So once hot a 0W-40 and 5W-40 are the same correct?

Some say that the most damage is done at start up, but is that mainly based on scaring damage? I would think that sludge and other damage occur at temp when the oil is pushed hard.

I have noticed on my oil cap a red colored light sludge. I liken it to tartar on teeth. Can this be good? Makes me think I should switch.

I've found a bunch of different opinions on Castrol Syntec. Some say it's good and some think it's junk.



and I still question if BMW brand Oil is Syntec in a different bottle?

Ugh...I'm confused. Maybe I should just switch to Mobil 1 5W-30

Originally posted by PunchIt:
Since my first post I have been searching and learing A LOT! Correct me if I'm wrong, but the first number (5W) is based on oil at cold startup right? So once hot a 0W-40 and 5W-40 are the same correct?

A 0w40 and a 5w40 will both be within the J-300 specs for a 40 wt oil at 100*C, which is between 12.5 and 16.3 cSt.
Hmmm...how did I miss this BMW thread?

Anyways, it's nice to see some more feedback on the BMW synthetic which I too stopped using this past summer after the same "increasing amount of consumption with each oil change" alerting me something was not right.

However, unlike your BMW, mine doesn't recommend 5-30 for anything over 5C (35F). Seeing as you have had good results with the Syntec 5-50, why not stay with it? With all the B.S. written here, I'll bet it's probably not too much off from M-1 in terms of OTC oil quality. They both have the same ACEA ratings. And just as your reasoning for a 0-40 and 5-40 being the same at temp., a 5-30 and 5-50 will roughly be the same viscosity at startup so this shouldn't be an issue. But, you will have added protection in film thickness at operating temperature and decreased burn-off.

Trying M-1 in anything less than the 15-50 will probably give you similar consumption as you have already witnessed because BMW's 5-30 is a very good oil (even though it's a group III)...guess your engine is now used to the 5-50 and I'd stick with it.
Dr. T,

First off, Happy New Year.

I decided to switch from the Castrol Syntec to Mobil 1 because, 1. I was having consumption issues and 2. because there were a lot of mixed reviews about OTC Syntec. Where as there seems to be very strong support for Mobil 1.

I believe I had only used the syntec 5W-50 2 or 3 times, and between those times I had switched back to the BMW 5W-30, and Syntec 5W-30 mostly cause my service advisor told me to use the BMW oil cause it was free on my scheduled changes, and that I should use my OTC syntec when I changed it myself.

Then someone on another board said the 5w-50 was too thick, and BMW only says to go up to a 5w-40. So I got worried.

I changed my oil yesterday to Mobil 1 0W-30, and was going to drive around for a bit and then change it again to Mobil 1 5W-30, to really help flush out any Castrol that could still be in there...but that would have been really OCD. My girlfriend told me I was nutz...she just doesn't get it.

I put some of the Castrol Syntec 5W-30 that was draining out of the pan into a 50ml tube to send in for analysis. I'm also going to send in a sample of Castrol syntec 5w-30 and a sample of the BMW 5w-30 to see how they compare. I have seen people questioning if they are the same oil. But haven't seen anyone actually give proof that the OTC Syntec is better or worse than the BMW oil.

That's about it.

Also, someone suggested that the red sludge was really just normal rust...but I bought a new oil cap and I'll see if it goes away with the Mobil 1.

PunchIt, I drive a 323i with a similar engine to yours (wish I had your horsepower). I have found that the Mobil-1 10W-30 has worked just fine in the engine. I used several viscosities and brands but the Mobil-1 10W-30 has been the easiest to find and has provided excellent wear numbers.

My engine also has that brown crust on the oil cap and inside of the valve cover. I have chosen to try the auto-RX to remove some of the built-up deposits that seem to have formed from the previous owner utilizing the BMW provided 15,000 mile oil changes and Castrol oil. I don't know yet if this will clean the engine since it's still in the infancy stages of application.

For what it's worth, my 2.5 liter engine (M52) doesn't use any oil at all and never has since I've owned it. I can't imagine that you'd do any damage to your engine in the short time that you used the Castrol 5W-50. I'd start sampling some of the synthetic oils that are approved for BMW's "long life" service and see if you consumption declines.
Interestingly enough, on M-1 website, under "choose your oil", for your car they list either a 0-30 or 0-40 for all temps and a 10-30 for temps over 5F.

On Castrol's website, they stipulate using a 5-30 for all temps (as you have) or a 10-30, 10-40 for temps over 5F. So I'm sure the 5-50 wasn't a problem.

Let us know the results!
Happy New Year to you!

I change my oil every 5,000 miles. I don't buy into that 15K crap. I'm sure the oil could go that far, esp. since I drive almost all highway. But....I have heard the filter won't hold up as well.

Also, I'm OCD with my car care, so that is why I decided to change the oil every 5K.

Dr. T.

Yes, I also saw that on the Mobil 1 site. 10W-30...I don't understand why BMW only recomends 5W-30. It's not like 10W-30 is too thick.

I found this thread, where there is a discussion about OTC Syntec vs. BMW oil
Links to other forums are not allowed, Please read board rules.

[ January 22, 2003, 07:32 PM: Message edited by: BOBISTHEOILGUY ]
PunchIt, my oil analysis showed that the oil could NOT go the 15,000 miles. I thought it was ridiculous to even try it on a group III oil as BMW was recommending. I settled in on 5,000 mile intervals. Mann-Hummel, the OEM supplier of oil filters for this particular line of engines did introduce a long-life filter specifically for the extended drain interval.

I was shooting the breeze with some service personnel at a BMW dealership in Munich just this past summer and they found it humorous that BMW of North America was now recommending 5W-30 oil for these engines. For normal uses they strongly recommended a 5W-40 and also sold a 10W-60 that they recommended for the select few people that choose to run the fire out of their cars on the autobahn.

If Mobil made a synthetic 10W-40 i'd use it. For now I'm using Mobil-1 10W-30 in winter and Amsoil 10W-40 in summer. Both seem to work well.

edited to correct spelling.

[ January 01, 2003, 05:33 PM: Message edited by: FowVay ]
Punchit: Welcome back to Boston and the snow. I'm sure we'll run into eachother on the track at some point.
Yes, I've considered the Mobil-1 0W-40 but at the moment I have a surplus of oils in my garage that I will need to use up before I buy any more. I am hoping to read many more analysis results of the 0W-40 to see how it is doing.

Originally posted by PunchIt:
Thanks MDV. Hope so. Need to find a track schedule. BMWCCA-boston maybe?



Autocross and the first school at Limerock is usually early April.
I wanted to give an update on the oil testing I had done by Blackstone labs.

you can see the results of the Syntec 5W-30 oil I was talking about earlier in the post.


[ January 22, 2003, 07:31 PM: Message edited by: BOBISTHEOILGUY ]
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