Single row. Vs. double row bearings

[southernstar]

No, you are not confused, IT is confusing. I believe that the settlement in the class-action suit lists vehicle VIN's and, of course, Porsche will know what original engine number matches the body. If your car is a 2001 with a single-row bearing, its VIN should be listed in the range of the ones included in the setllement.

Porsche's parts catalogue lists a cutoff date for the dual-row bearing based upon the engine's serial number: essentially, the final 5 sequential digits of 11237 for the 3.2 and 12851 for the 2.7. This is, of course, assuming that the engine was not replaced or rebuilt after the introduction of the single-row bearing, in which case it would have the 'updated' single-row, even if it was originally manufactured with the dual-row. A Porsche remanufactured engine will have the letters 'AT' in the serial number; however, some engines have been rebuilt by dealers (or elsewhere) and while the original serial number will be on the engine, the IMS shaft and bearing could have been replaced.

The engine serial numbers are, as indicated, the cut-off date for the dual-row and accordingly, all engines manufactured after those numbers should have the single-row IMS bearing. Ones prior to that may have either, although it is my understanding the the single-row bearing was a mid 2000 model-year update on the 2.7 and 3.2 made late in the 1999 calendar year.

Ultimately, this means that as far as 2.7's and 3.2's, you will only be safe to conclude that it was manufactured with a dual-row bearing if the engine was manufactured in 1998 (represented by the letter 'Y' in the engine serial number, just prior to the final 5 sequential digits). An engine with a 'Z' preceding these digits, will have been built in 1999: if early that year (i.e., prior to the introduction of the new bearing in late 1999) it will have the dual-row bearing. After that, it could have either (the same for engines built in 2000, which have a number '0' prior to the final 5 sequential digits, or 2001, which will have the number '1' at that location). Again, any engine serial numbers afther the ones listed above, which again is the cut-off point for the dual-row, will have single-row bearings.

If your engine was built in 1999, as the serial number denotes only the year and not the date of manufacture, you cannot be absolutely certain whether it was built before, or after the introduction of the single-row bearing. If your 2000 was assembled in 1999, however, it will be far more likely to have the dual-row bearing, as there appears to have been some significant lead-time between the assembly of the engines and the installation in car bodies. As I have indicated in another post, the engine in my 2.7 was manufactured in 1998, but the assembly date for my car was in August 1999. If your car's assembly date was in late 1999 and your engine serial number shows that it was built in 1999 (remember, the letter Z), I believe it is safe to assume that it will have a dual-row bearing as engines manufactured in late 1999 were likely not installed in bodies until the year 2000. Clear as mud?

Lets put it this way, if your 2.7 or 3.2 was sold and initially registered as a 1999 in a country where the model year is based upon the date of manufacture (as I understand it, in the UK and most of Europe), then you should have the dual-row bearing. Support for this proposition can be found in Porsche's indication that the single-row bearing was not introduced until the 2000 model year. Hence, the same should be true for 2000 model year 2.7's and 3.2's sold in North America, if the manufacturing date of the car was in 1999.

Brad