Rangers used rear axle ABS VSS sensor thru 2000 so 2001 should be first appearance for OSS
BUT..................there will be exceptions to that, i.e. 2.5l Rangers didn't end until 2001.5, so mid-year, and they used rear axle VSS, their replacement, 2.3l Durtec 2001.5 and up would use OSS
4.0l OHV would use rear axle VSS, 4.0l SOHC OSS , but again there are 4x4s and they use transfer case VSS and OSS
So is vehicle model and year specific
They are the same type of sensor, VR sensors, self generating their own power and output AC volts
The name change was for Output shaft speed(OSS) sensor, because there were other speed sensors in the automatic transmissions reading other shaft speeds
VSS, vehicle speed sensor, was generic term for what an electric speedometer was using.
VSS was used on output shaft from 1995 to 1997 for electric speedos, gear driven like speedo cables
In 1998 rear axle ABS sensor was used for speedometer and called VSS because of that, it was just rear ABS sensor before that, lol.
OSS sensor runs to Computer(PCM) and is used for the shift control software if there is an automatic trans
PCM also converters the OSS Pulse Per Mile to the standard Ford 8,000PPM and sends it to speedometer and cruise control
The rear axle VSS went to ABS and GEM, GEM converted it to 8,000PPM and sent it out to speedo and cruise
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