Q: Are there 1 or 2 RABS valves on my truck? on 1993 Ford Ranger

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Emergency Brake light & ABS Brake light comes on when applying brake, then stays on. Took my '93 Ranger in for a Dianostic Test, which showed a Code 4. Received quote of $800 to replace the RABS valve.

Thinking the parts @ $490 high, I checked for the part online and am now confused. Are there 1 or 2 RABS on my truck? Also 2.5 hrs + $490 parts seems high. Any thoughts? Thanks for your help! emartin
(1) Answer
If it's got a single speed sensor in the rear diff. pull it out and clean off the debris and re-install. might want to do a rear diff fluid change to ,at the same time (when it's warm is best).