ATF change, ATF lab report, ESSO no longer recommended by BMW or GM

[John Galt]

20,000 mile update: transmission is shifting perfectly well with no issues.

My 2001 3.0i X5 has 83k miles on it, and I decided to change the transmission fluid, even though BMW says the fluid is “lifetime”. BMW does not define what “lifetime” means, but they don’t give warranties past 100k miles. Think about that.

My primary drivers for changing the fluid were that 1) GM uses this exact transmission (A5S390R) in other cars and recommends 100k mile ATF changes 2) ATF just does not last forever (what does?) and 3) I want to get at least 200k miles out of this truck.

While trying to decide what fluid to use, I thought about using the originally recommended Texaco ETL 8072B (also by ESSO?), but, both GM and BMW say that this fluid should not be used, and instead BMW says that their part 83220397114 should be used and GM says that Dexron VI should be used. Presumably, 83220397114 is Dexron VI.

Question: I’ve seen data that says that 8072B is Dexron III, and I’ve seen people say that it is a full synthetic, but I’ve never seen any documentation. Can anyone verify that 8072B is really a synthetic (Group III or higher)?

With both GM and BMW recommending Dexron VI, I did not feel the need to go with the 8072B fluid, but, since I did not find anyone online that had switched their A5S390R to Dexron VI, I decided to go with Redline D4ATF. It seems to be the highest quality (group V base) ATF out there where I can find plenty of people using it without problems in their A5S390R. (yes, I do know that it is not certified Dexron III or Dexron VI)

If I could have found several people that went with Dexron VI in their A5S390R, I probably would have gone with Valvoline’s full synthetic Dexron VI (does anyone know what base stock that is?). Judging by the fact that Valvoline claims a full synthetic Dexron VI and pretty much everyone else says their Dexron VI is a blend, I have to assume that Dexron VI does not automatically equal full synthetic (as some people seem to claim).

In any case, the fluid change went very easily. I drained the fluid, dropped the pan, changed the filter, put everything back together and filled it per the BMW procedures. It took about 6.5 quarts. Even though it is a different tranny, the fluid and pan looked about like this, which, while the oil was very black, the plan was cleaner than I was expecting. Two days later, I did another quick fluid drain and fill (no filter change) to get at most of the rest of the old oil. It took six quarts the second time (no pan drop or fitler change). One thing to watch out for: part of the gasket of the original filter stuck up in the mounting hole and I had to reach in and pull it out. It was not a big deal, but it would have been if I had left it in there.

I sent the oil from the first change into Blackstone for analysis. Here are their comments: “Judging by what we found in this sample we don't think your BMW's transmission fluid has been changed before. All wear is above average but copper was the most out of line. Iron, copper, and tin all come from the clutch plates, while aluminum is from the torque converter. Silicon is likely from sealers used when assembling the transmission. Insolubles at this level may show sludge in the system. We think a few short oil runs should clean up your transmission. Try 10,000-15,000 miles on the next oil. The TAN read 3.6, showing the oil was very acidic.”

Here are the interesting numbers from the report:

Aluminum 90
Iron 192
Copper 417
Tin 16
Silicon 51
Insolubles 0.3%
TAN 3.6

Here is a link to my full report: D67388.pdf - Windows Live

None of this is very good, especially the TAN. I think that shows that BMW’s lifetime fill is really intended to mean 100k. I do not think my transmission was going to go another 100k with numbers like this at 80k. I suppose mine could be a fluke, but I doubt it.

The transmission was working fine before the change, and it is working fine now. Maybe it shifts a little quicker and smoother, but not much.

[koister2001]

Thanks for sharing your experience!

[X5 Meister]

Great notes. Personally I would have just gone with what BMW currently specs for the car, but to each his own. Great idea to send it to blackstone.

[JCL]

Good post, and thanks for the information on the lab report.

A couple of comments from my experience with oil and hydraulic fluid sampling:

The lab report, while interesting, becomes much more valuable if you can plot a trend line from multiple samples. Isolated numbers, by themselves, don't tell very much. For the total acid number, you could take a sample of the original factory oil (from the dealer) and see what the change has been. For the other items listed, they weren't zero in new fluid and it helps to see when they climb, when they stabilize, and when they spike. You want to change it before they spike, essentially. If the aluminum got to 80 during break-in, for example, being at 90 now isn't an issue. If it was 5 for the entire life of the transmission and went to 90 last month, then now is exactly the time to change the fluid.

Did you do any large particle analysis? The dissolved solids info is fine, but I would look for a particle count as a key indicator.

My other comment is about the comparison with the GM transmission. I have no doubt that the mechanicals of the transmission are the same as the GM product (or ZF, for the ZF-built transmissions). What BMW does do is add their own control package, and electronics. Those electronics and sensors are programmed to provide different shift points, and different shift characteristics than the GM electronics (which is why BMW puts them in there). The way in which a transmission shifts has a large effect on the wear and heat resulting from a shift. Essentially, a firmer shift reduces the time the clutch packs are slipping, reduces heat, and so on. All of that extends fluid life. A soft, slow, shift that slips the clutche plates more results in faster wear of the clutch plate material and disks, and much more heat (which breaks down the fluid much more quickly). While the transmission durability is likely similar between the GM and BMW versions, the above means that not everything can be extrapolated. That doesn't mean that you shouldn't change your fluid if you want to, but it means that the GM recommendation for 100,000 is simply one more data point, and not an absolute truth.

I was very glad to see that after you changed the fluid, you did a second change. If you are going to change it, it makes sense to get more of the old fluid out and if you got 50% of the old fluid out each time, after two changes you are at a 75% change, considering the amount of fluid that stays in the transmission/torque converter when you drain the pan.

Thanks again for your post.

[realchef]

Originally Posted by JCL

Good post, and thanks for the information on the lab report.

I was very glad to see that after you changed the fluid, you did a second change. If you are going to change it, it makes sense to get more of the old fluid out and if you got 50% of the old fluid out each time, after two changes you are at a 75% change, considering the amount of fluid that stays in the transmission/torque converter when you drain the pan.

Thanks again for your post.

JCL,
Is there a way to perform a 100% fluid change at one time.

[JCL]

Originally Posted by realchef

JCL,
Is there a way to perform a 100% fluid change at one time.

If you drain the transmission, torque converter, lines, and cooler, then yes. A sure way of doing it is to remove the transmission. Not worth it IMO.

[John Galt]

Originally Posted by realchef

Is there a way to perform a 100% fluid change at one time.

I looked into this. The torque converter does not have a drain, so you can't easily get the fluid out. The only options involve opening up the ATF cooler lines and swapping out the fluid while the car is running (many shops have a system that will push fresh fluid back in while it takes out the old fluid via the cooler lines), but I've hear of lots of bad results from those things, so, I don't think there is an easy way to get all of the fluid out in one shot.

However, doing the second fluid change, just drain and fill only, was very easy and took less than 30 minutes.

[Werewolf]

Originally Posted by John Galt

I looked into this. The torque converter does not have a drain, so you can't easily get the fluid out. The only options involve opening up the ATF cooler lines and swapping out the fluid while the car is running (many shops have a system that will push fresh fluid back in while it takes out the old fluid via the cooler lines), but I've hear of lots of bad results from those things, so, I don't think there is an easy way to get all of the fluid out in one shot.

However, doing the second fluid change, just drain and fill only, was very easy and took less than 30 minutes.

John,

I spoke with a very knowledgable / trusted BMW independent and he said the lifetime ATF BMW uses is complete BS. In the 2001-2003 models the ZF tranny used is a weak point with tranny life of 100-150k. Unless BMW has reinvented the tranny and not told anyone; the lifetime oil bit is a marketing ruse. The metals grind and the shavings need to be emptied with the oil. I guess BMW wagers that 4-5K repair once every 125k miles or so is not enough to cause owners to riot.

[John Galt]

Originally Posted by JCL

While the transmission durability is likely similar between the GM and BMW versions, the above means that not everything can be extrapolated. That doesn't mean that you shouldn't change your fluid if you want to, but it means that the GM recommendation for 100,000 is simply one more data point, and not an absolute truth.

I understand that, but given that GM made the transmission internals, and they use that same package in their cars, it does give what they say a lot of weight. I don't think that a reprogrammed shift pattern is going to take the fluid from lasting 100k miles to lasting forever. Whatever you think about that, the high TAN alone from my fluid says it was time to change, despite what BMW says about the fluid not needing to be changed.

Here is a link to my full report: D67388.pdf - Windows Live

[JCL]

Originally Posted by John Galt

I understand that, but given that GM made the transmission internals, and they use that same package in their cars, it does give what they say a lot of weight. I don't think that a reprogrammed shift pattern is going to take the fluid from lasting 100k miles to lasting forever. Whatever you think about that, the high TAN alone from my fluid says it was time to change, despite what BMW says about the fluid not needing to be changed.

Here is a link to my full report: D67388.pdf - Windows Live

Thanks for the full report. A baseline number would be really helpful as well, if anyone out there has a low-mileage Blackstone lab report on the factory fill fluid.

In the 'good old days' (prior to electronic shifting controls) we dealt with automatic transmission fluid overheating by installing 'shift kits' from B&M and other performance parts outlets. They were essentially revised check valves and springs for the transmission valve body, which reprogrammed the shift points for higher revs, and firmer shifts. They were good for trailer towing as well as performance V8 applications in muscle cars. They reduced fluid temperature, and the likelihood of clutch damage. It is not the shift point (in rpm) that matters as much as the shift characteristic, since clutch plates wear when the shift is happening, and not between shifts. That is so true, that for some applications engineers commonly measure transmission life by the number of shifts, not the number of hours or miles. So, IMO, changing shift characteristics has a significant effect on fluid life.

I fully agree that it doesn't make the fluid last forever. Just like the famous story of the pack of gazelles in Africa that is pursued by the lion, however, you don't have to be the fastest gazelle. You just can't be the slowest. Applying that to transmission life, my point is that it doesn't have to last forever. It just has to exceed the useful life of the rest of the vehicle, whatever that may be deemed to be.

The Dexron specs (which have been improved since your vehicle was produced) list various oxidation and stability tests. The TAN indicator varies by transmission manufacturer, but some published numbers I have seen are that TAN cannot increase by 3.0 or 3.25 over initial baseline numbers, whatever that baseline number is. I don't know what the initial TAN number is for your fluid, but there are other oils out there on the market in the 1.5 range. By that calculation, your fluid was about halfway to the change limit. All of this is an estimate, but I wouldn't say that your fluid was dangerously high. It was trending towards a replacement point, absolutely.

Interesting topic, thanks for the post.