I had a feeling that,,,
 

I recently purchased a 99 Tip with about 133k`s.I couldnt get any history of the IMS being re and re until a few weeks ago and it wasnt. So, after much research I sent the car to Mantis to have the IMS ( LN ) and rear main done. As it turns out the bearing was fine. I had a feeling that it was maybe ok after the first oil change I had done.
Anyway that works done now. I also had a Mantis under pulley installed, new plugs and tubes and a new trans filter. Ouch !:dance:

another testament to the durability of the M96
Car was probably maintained properly and driven

The shop manager told me the M96 double row bearing with a tip seemed to be the least in failure. But that was just his opinion.

He is correct.

I've been down sort of the same road. Except the shop I finally chose to replace my IMS turned out to be manned by jerks. Estimate to replace IMS on my 2000 2.7 with tip, was $1800.... "Are you sure?" "Absolutely! I've done plenty of um" 2 days in, it went to $2100. After being in the shop for over a week, $2800 at pick up!!!! 1 week later, axle shaft bolts sheared because of improper torque. Anyway, long story short. it took another $1200 at a more reputable shop to correct the "repairs" done at the first shop. Broken exhaust studs, damaged exhaust heat shields, Replace and re-torque axle bolts, replace axle seal damaged. Anyway sorry for the rant.

Anyway.. The reason for my reply... Is there a definitive cutoff when Porsche went from double row to single row IMS bearings? The whack job shop who did the work said I had a double row, but frankly, I have no reason to believe he can even count to two.
when the bolts went south.

I would be a little concerned about the install of the IMS...

What is the name of this shop?

:D

I don't think it would be very ethical for me to mention Greens Motorsports in Springfield VA. That just wouldn't be right..... Ooooooops!

Anyway. Anyone know about when Porsche went from the double row to single row?

Depends on the Model and where it was built.

For a 2001 S built in Finland it seems to be some time after about vin(Last4 digits) serial# 1000 if I recall correctly.

You can look up the IMS lawsuit on these forums for a comprehensive list but generally if your VIN is excluded its likely because it has a dual row IMS.

Like many things Porsche, the answer here is "no". Porsche transitions engineering design changes on the fly, so somewhere in 2000-2001 they changed over from dual to single row, which necessitates that any shop prepping a car from those model years has to take the car apart and look to see which one is actually in the car.

Or it is too old, or the car has been resold multiple times, or it has a replacement engine, or......

I would not place a whole lot of credence on whether the car has been excluded or not.