Hi everyone -

I just went through this with the authorized dealer. Part number for ETL 8072B was superseded in BMW part system and guess what, it is now Dexron VI. I originally ordered ETL 8072B but it never came in. So, my trusty part guy at the dealer checked part number again to find this.

This makes good sense as it is a GM transmission after all and I suspect ETL 8072B was nothing more than Dexron III variety, not even synthetic kind.

Now, when I replaced fluid at 67,000 miles, frankly fluid was in such a bad shape and now I understand why so many BMW auto box fails. Fluid was black (lost red coloration all together) and well past useful life. It was fortunate that I did not find any metal shavings, etc. I have absolutely no idea why BMW does not recommend a regular replacement - box manufacturer, GM, does.

I chose Valvoline Dexron VI as it is full synthetic and cheaper than Castrol (I use Mobil 1 wherever, whenever I can but Mobil's Dexron VI is a synthetic blend and Mobil 1 full synthetic ATF really should not be used for this box).

Difference it made was nothing short of stunning. Now box is ultra smooth and shift is super silky.

I did remove the pan but did not replace a filter - I ordered aftermarket filter to one of those BMW specialists. Compared to the OEM part, this replacement (German name, made domestically) was obviously sub-standard and even missing an extension to reach to the bottom of the pan as well as a support against the pan to hold it in place. I will order OEM filter to the dealer and redo this. When you drop a pan and refill, do a refill one extra time after engaging gear - this will allow more of oil trapped in torque converter to be replaced. First fill (after engaging gears) showed darkened fluid. Second fill gave much lighter (red) coloration.

Box holds 9 liters and first fill (pan drop) will initially allow only 4 liters of new fluid. Engage gears and top-off - this will introduce another 2 liters. Then drain and refill - 2.5 liters. So all together you will need 8.5 liters.

All I can say is that the difference is nothing short of amazing. If I knew, I would have done this every 25,000 miles or so.

Speaking of fluid, BMW's schedule for engine oil change is, mandated by the government to reduce ownership cost, way too lenient. I would change much more often. This manifested in clogged oil separator and stranded us one day. We have 2 911s. Porsche, likewise, changed oil change requirement to 20,000 miles - absolutely positively way too long and PCA adamantly recommend shorter oil change intervals.

I love German cars and we tend to follow manufacturers' recommendation/requirements little too strictly. They used to disclose more specifics, but now we get these mysterious ETL 8072B spec. And lifetime fluid that designed to last 50,000 miles, maybe. Whole point is monopolization of after-sale services, which is a huge cash flow to any manufacturers. We all know dealers make money from servicing, not from sales. BMW really wants to sell replacement auto box for $6,000 a pop, I take.

Anyhow, I hope this helps.