I have a 2014 LS460 and am doing the brakes. I have a few questions.
1. Should you always replace brake wear sensors when replacing pads?
2. I bought a rear brake kit with rotors, pads, and brake wear sensor. The kit only came with one sensor. Is this right? I went to auto zone to get another rear sensor thinking I needed two and they asked me if I needed rear right or left. Is there a difference? One side was double the price as the other side. That brings the question is there a specific right and left for the front too?

TIA

 

1. No, unless you had brake wear indications on dash (meaning one or more sensors are burnt thru and needs to be replaced). Good sensor can be pulled from old pad and reinstalled on the new one. If you're careful, the sensor mounting hardware (little weirdly shaped holder thingie) is reusable at least once.
2. Some LS only have one side 'sensor'ed' - thus only one sensor for rears. Other LS got all 4 wheels sensors. No way to know without e.g. your vin or at least more detailed model description.
Yes, sensors for all 4 (or 2) sides are different, mounting is a little different, length too.

 

I replace wear sensors at each pad change (but use OEM where possible). When I did my 2008LS it only had one wear sensor at each end of the car. This may not be the case for other years.