How long do FSR last?
 

I just replaced mine.
Looked like it was dated 34th month of 2011.
Since the X5 was built in 2003, I'm guessing it had been
replaced at least once.

Anyone care to comment on the lifespan of these hedgehogs?

I think it's hit or miss. OEM ones last a lot longer than aftermarket by rule... but they can still fail at pretty random ages/mileages.

My 2001 oe factory FSR failed at ~ 50,000 miles/ early 2006.
I had the 'then version' of 'extended maintenance', and the dlr R&R'd that original.

Now, I have 113,000 miles, and that replacement still works, knock on fookin wood.
I cringe just admitting that that replacement was so long ago. :yikes:
GL, mD

As for the symptoms, mine seemed to vary in output air flow.
What used to be plenty, was now a whisper.
The digital fan speed indicator didn't jibe with the output flow.

Is that an indication of failing FSR?

New FSR will part your hair now!
Well, when I had hair, that is.

I still have the OE one running fine. Watch now it will fail.....

If you run the blower at a low speed I think you will use the FSR more since more of that energy is converted to heat, whereas if you run the blower at a high speed less of the current is converted to heat by the FSR, but since the blower motor is spinning at a faster speed, the blower motor will expire quicker.

You choose what you want to replace. Blower motor of FSR. If I don't need to run the blower motor I just keep it off.

Original lasted 78,000 miles, second OEM went 81,000 miles, third OEM has lasted 166,000 miles. On the third, the dealer did tell me BMW had "beefed it up" because they were replacing too many under warranty. Living in Texas, the blower motor is used 363.76 days per year - maybe more :bustingup

2002 X5 3.0 324,950 miles (almost another milestone)
2014 428i 28,100 miles

2004 325i sold at 123,600 miles
2001 325i sold at 66,000 miles (also had FSR replaced under warranty!)

1970 Firebird - Under restoration

still have original FSR and blower motor at 118,000+ miles.

Amazing.
Living in Texas, whole lotta fan going on!