I just purchased an '08 Ram 1500 Quad cab Hemi. I was looking under the truck and noticed an electrical connector that is connected to the top of the rear diff pumpkin. What is in the rear diff that requires an electrical connection? I asked the sales person if it came with a liimited slip rear axle and I got the usual answer "all the Ram Big Horn edition's come with it standard". I can't find any information about it in my manual. I emailed Dodge with my VIN and all they replied with was that the truck came with a 9.25 LD axle, thats all they told me about it.
Thanks for any info you can provide.

 

It's the speed sensor. Itprovides a signal foryour speedo, cruise controlas well as helps control your ABS. It's nothing more than a hall effect sensor (magnet) that senses a coged wheel that is mounted on your pinion inside the differential. As the reluctor ring (coged wheel) turns on the pinion the teeth pass by the sensor and it sends a pulse to the computer which then does it's magic and turns it into your speed based on pulses per mile.