I've been having oil analyses done periodically to try to find a suitable oil and change interval for our MINIs (we have two 2006 'S' cabrios). About 6,000 miles ago, I switched from the standard MINI oil ("German Castrol" 5W-30 full synthetic) to a non-petroleum bio-based oil (Renewable Lubricants Inc.'s Biosyn 5W-30). I decided to try Biosyn because I wasn't happy with the numbers I was getting with the Castrol, and Terry Dyson (of Dyson Oil Analysis) recommended Biosyn, because it's been doing really well in other "problem engines" like the one in the new Audi RS4 and BMW twin-turbo 335. Evidently the RS4 and 335 have been absolutely *killing* all of the petroleum-based synthetic oils that owners have been using (especially the factory-recommended oils).

Anyway, here are the numbers. In all cases, the first number is for MINI Castrol 5W-30 after about 12,500 miles (this was the factory oil, left in until the OBC said it was time to change it).

The second number is MINI 5W-30 installed by the dealer, and left in for 9,000 miles. (After 9,000 miles, the OBC was still reporting 10k to go, but I wasn't about to let it go that long).

The third numbers are with the RLI BioSyn after 6,000 miles. I just pulled a sample, rather than changing the oil - the same oil is still in my car. I pulled a sample early since it's my first experience with the oil. I'm going to change it at about 8,000-9,000, and I'll pull another sample for analysis
then.

The fourth numbers are the same BioSyn as the third test, just with an additional 4,000 miles on it (10,000 miles on the oil, 32,900 miles on the car when the sample was pulled.

WEAR METALS (parts per million, lower is better)
Iron - 81, 18, 8, 18
Copper - 38, 15, 5, 10
Tin - 3, 3, 0, 0
Lead - 29, 9, 3, 7
Chromium - 4, 2, 1, 1
Nickel - 6, 4, 2, 7
Aluminum - 13, 4, 2, 3

CONTAMINANT METALS (parts per million, lower is better)
Silicon - 71, 5, 2, 4
Sodium - 41, 24, 11, 17
Boron - 15, 53, 16, 13

TOTAL ACIDS NUMBER (TAN) (lower is better)
3.59, 3.78. 1.76, 3.27

FLASH POINT (degrees Fahrenheit, higher is better)
320, 300, 410, 370

FUEL DILUTION (percent, lower is better)
1.29, 1.46, 0.107, .722


Even though the wear and contaminant numbers are great with the BioSyn, anything would have been an improvement over the first results, since that was the break-in oil. Terry thinks that once the last remnants of the Castrol is out of the engine, we can get these numbers down even further on Biosyn.

What I'm absolutely thrilled about are the TAN, Flash Point, and Fuel dilution numbers. The TAN for the first two samples show that the Castrol was pretty much at end-of-life by the time I changed it. The TAN for the BioSyn is less than half that of the Castrol, and the additive package in the Biosyn was still going strong as well.

The flash point had also gotten dangerously low with the Castrol, to the point where you're going to have the oil film baking off and leaving deposits on the hottest parts of the engine. The flash point for the BioSyn was 80-100F higher, and an excellent result for any oil with 6,000 miles on it.

But the fuel dilution is the biggie. The high fuel dilution numbers with the Castrol were probably the cause of the high TAN and low flash point, since fuel contamination in the oil can cause both of those. The fuel dilution with the Biosyn was less than one-tenth of what I was getting with the Castrol.

Fuel dilution causes problems with supercharged, turbocharged, and direct-injection gasoline engines. Because the cylinder pressures are so high, even before the air/fuel mixture is ignited, that you can get fuel leaking past the piston rings into the oil. I'm really curious to see what kind of fuel dilution numbers people start getting with the R56, since it uses direct-injection.

I'll be pulling another sample of the Biosyn that's in the car now in about six weeks, and I'll update the post when I get the new results.

UPDATE - Just added the numbers for the 10k mile BioSyn test results (fourth column in the test results). All of the numbers were higher than the 6k mile test, which doesn't surprise me, since it's the same oil and I didn't add any top-off oil in the 4,000 miles between the test. The fuel dilution is higher than I'd like at 0.722%, but that's still only half the dilution I was getting with the MINI oil after 9k miles. Flashpoint and viscosity were still good. The TAN was up to 3.27, so the oil was due to be changed. (The TAN was still lower than the MINI oil after 9k, though). I'm still playing around with the air filter to see if I can get the fuel dilution numbers lower.

Another poster in the thread was asking if the early crappy test results with the MINI oil were just because the car was still fairly new, so to check that out, I refilled the car with MINI oil when the BioSyn came out at 10k. I have about 4,000 miles on the MINI oil now, so I'll be pulling it in about 5,000 more miles and see how the results compare to the earlier 9k MINI oil test.

Right now, I'm comfortable using the BioSyn for 10k mile intervals, although the oil was just about due to be changed. I'll probably stick with 10k intervals, but I'd like to see if I can get the wear numbers and fuel dilution down a little farther.

 

ill keep a close eye on the results... i should get some of the amsoil 5w30 stuff sent to you so you can tell me how my oil is doin

 

You are gonna get pummeled if the "shear" values aren't comparible. There are those around here that "swear" that if you don't have these as equal numbers you aren't doing the best for your engine.



Good numbers BTW, that is nice to see...

 

Just send it to Terry Dyson (www.dysonanalysis.com). He's the guy that does all my testing/interpretation. Great to work with, fast turnaround, and he gives you a detailed audio recording of his interpretation, instead of just generic "high/normal/low" standards like you get from some labs.

I know - I'm waiting for the onslaught. Since RLI is a small company with virtually no sales volume compared to the big companies, I don't even think they've submitted their oil for ACEA testing. The Biosyn meets the API specifications as far as viscosity goes, but I don't think it's been given an official rating like SH, SJ, SM, etcetera.

I'm still comfortable using it because I'm doing periodic analyses to check up on it. Otherwise, the last thing I'd ever do is take a brand-new oil that I've never heard of and leave it in the crankcase for 10,000 miles without checking it. (Especially one that's made out of vegetable oil!)

 

Well, as long as you are prepared, you should be GTG...

 

Thanks for the post Scott.

I am very interested in starting to do oil analysis, since the Merc (Sprinter) takes 9.5 quarts, and it is worked pretty hard. Might as well start the Clubman off right also.

 

Great post Scott

Nice to see someone checking out some alternatives

How much is it a qt?

I change my oil at least every 3k sometimes much sooner as I track the car.

 

I should also point out that I wouldn't be going through the trouble and expense of the oil analyses ($180 so far) if not for two things:

1) We have two virtually-identical MINIs, so I can use the results from one car to develop an oil type/interval plan to apply to both cars, and

2) We tend to keep our cars for a very long time. If I only had one MINI, and was planning on selling it after 2-3 years, I'd take the money I've spent on oil analyses and just change the oil every 6,000 miles instead, and would probably come out ahead financially in the long run.

 

The RLI Biosyn 5W-30 is almost $10 a quart, but that drops down to about $6.85 if you buy it in bulk ("bulk" meaning a 5-gallon pail - you don't have to buy a 55-gallon drum). I also like the fact that it's not petroleum-based.

I autocross mine, but I realize that's causing nowhere near the stress of the track racing you do with yours. The Biosyn is enjoying quite a bit of success in race cars as well, though.

 

For us layman, can you tell me how you would rate the comparison between the Castrol 5w30 syn and Mobil 1 Extended Performance synthetic for use in the mini? I have read several favorable articles on Mobil 1 and am considering changing the oil right after break in to the Mobil 1. thoughts on Mobil 1 5W30?

 

When it comes to this stuff, I'm basically a layman, too. The only results I know anything about are the ones from the analyses I've had done. I've done a bit of studying on the subject on my own, and I've learned a lot from my conversations/e-mails with Terry Dyson, but my knowledge is no substitute for a good experienced analyst.

My impression of Mobil 1 is that it's a good oil, but I feel the same way about Castrol, too, but I'm convinced that the Castrol oil that MINI recommends would have been completely *trashed* if I left it in anywhere near as long as the OBC is recommending.

All I can suggest is trying out the Mobil 1 for 7-8,000 miles, then pulling a sample and sending it to Terry. He'll be able to tell you in great detail how it's holding up and whether it's suitable for your needs.

 

Look forward to seeing your results. Been taking my car to the dealer on the OBC numbers on the Mini so far but my wife's new SUV doesn't have the paid maintenance. Did I miss where you get this oil? (Just bought Catrol Syntec (not German - wasn't available) for my wife's MDX).

 

You talkin' to me? You talkin' to me? You talkin' to me? Then who the hell else are you talking... you talking to me?

 

Great info, it is nice to see someone thinking outside the box.
Keep us posted on your results from future oil analysis.

 

Sorry, I guess I should have included that information. I'm getting the Biosyn oil directly from RLI here. I don't know if it sold in any stores, but if it is, I imagine it's only at stores local to them in Ohio.

 

Great info. Good to see some other analysis numbers. Your numbers show some great improvements as you change to better and better oil. I'm at a crossroads with mine right now. I may just run another series of Castrol, and then move on to a boutique oil.
Here was my analysis last fall...

 

Interesting experiment - I'll keep an eye on this thread. Funny, Castrol R, a high performance castor oil-based racing lube, was the wonderful smelling top dog in the old days. Well, wonderful if you love old race cars.

 

This is really interesting. Thanks for sharing what you've learned.

 

Really interesting - I wonder what property of the Biosyn is driving the huge drop in fuel contamination, and what the other effects of that property might be?

This was very timely - I'm due to take Blimey in for dealer service in a week or two... I'm doing "in between" changes with German Castrol, probably about 8K on what's in there now. I should pull a sample for analysis before I take it to the dealer.... how big a sample does Dyson need?

 

About two or three fluid ounces. Just make sure to drive the car to get the oil mixed and up to operating temperature before taking the sample.

Give Terry Dyson a call at (903) 883-4661 and he'll send you a couple of sample bottles. You should have them in plenty of time before you take Blimey into the dealer.

 

Already ordered my kit.

 

If you think you're going to be pulling samples in-between oil changes fairly often, I really recommend Blackstone's oil pump. You just screw the sample bottle into the pump body, stick the tube down the dipstick opening, and two or three pumps will completely fill the sample bottle. It really makes it easy to pull a sample when you're not draining your oil.

 

I have a Griot's oil extractor - a little messier... but will work fine.

 

i have been told to use royal purple. you might want to check it out.

 

Mailed my sample to Dyson on Monday, got an email with results tonight - fast turnaround. I am BLOWN AWAY by the level of interpretation and recommendations Terry gives you above and beyond what you get with a "plain" oil analysis. My datasheet had 13 comments on it explaining what various numbers actually meant and what might be causing them, the the whole thing came with an audio file several minutes long that walks through all the results in great detail as well as recommendations. Plus he asked for more specifics on the fuel, filters, additives I'm using, type of driving, whether or not I track the car, etc. so he can provide even more specific recommendations.

I HIGHLY recommend Dyson for this service - not cheap, but you get what you pay for.

Thanks for the recommendation, Scott.

By the way... I can sense a 5 gallon pail of RLI BioSyn in my future...