(Ignoring 00-04 fuel pump cap tab cracking and oring issues).  I’d guess alternator but have never kept track.  

Alternator sees more heat cycling, isn’t sitting in a “cooling fluid” (a tank of gas like a fuel pump), and it has more of a “computer” with the built in voltage regulator.  

I’ll ask my parts guy how many alternators vs fuel pumps are in the regional warehouse for fun. 

Alternator

 

 

In my years at Subaru dealerships, I can't remember the last time I've seen a fuel pump fail. There was a recall on them a few years ago. Sometimes we replace the whole assembly, but even that is usually due to rodent damage.

Alternators aren't exactly common either, but it happens.

 

 

Out of curiousity...I have a 2015 Outback VIN in my catalog right now. I have 2 alternators here, and there are 53 in the warehouses nationwide. I have zero fuel pumps or pump assemblies, and there are 4 assemblies in the warehouses nationwide. Now, that doesn't take into account fitment (if that part number for alternator fits a lot more cars than the fuel pump).

Edited June 10, 20241 yr by Numbchux

4 hours ago, Numbchux said:

Alternator

 

 

In my years at Subaru dealerships, I can't remember the last time I've seen a fuel pump fail. There was a recall on them a few years ago. Sometimes we replace the whole assembly, but even that is usually due to rodent damage.

Alternators aren't exactly common either, but it happens.

 

 

Out of curiousity...I have a 2015 Outback VIN in my catalog right now. I have 2 alternators here, and there are 53 in the warehouses nationwide. I have zero fuel pumps or pump assemblies, and there are 4 assemblies in the warehouses nationwide. Now, that doesn't take into account fitment (if that part number for alternator fits a lot more cars than the fuel pump).

Awesome. Thanks Chux, very much appreciated. 2016 is the year I’m currently thinking about so I might buy that same alt you looked up If I can’t find a low mileage used OEM. Currently 200,000 miles started life as a southern car, zero rust, in impeccable condition so there’s a decent chance of a lot more miles so I’ll likely replace the alt preemptively.