Even if you can determine the alternator from a build date, how do you know if a previous owner(s) hasn't replaced it with a different brand alternator. I have a Valeo alternator that I just put in a new regulator (OEM Valeo), but I have a spare BOSCH which I also put in a new regulator in my spare part box.

The only way to check is to remove the alternator and confirm visually what is installed.

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2006 Infiniti G35
2001 BMW 3.0I E53 X5 Build date 08/2000 SOLD
Lotus Europa 1970 Destroyed by fire
Lotus Europa 1970 S2 Renault Powered
Lotus Type 52 1970 Twincam Webers Powered
PORSCHE 911 Targa 1982 The Garage Queen
Audi Avant donated to Kars for Kids
BMW 525IT Sold
Audi 4000CS Quattro Sold
Jensen Healey Lotus Powered Sold
Opel 1900 Sold
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