A single clunking noise from the rear after each time the car comes to a stop

Pads last so long on the Prius, and I would think even more so on the Prime since it can do more regenerative braking with the larger battery. So assuming they didn't grind that much off the pads they should still be good for a long, long time.

 

If you have a problem in future, request the same mechanic. It might mean a bit of a delay, but he did good work and a request by name might be a feather in his cap. A friendly relationship built on mutual respect is what most of us dream of.

 

Probably no ID of the mechanic on the invoice, might be more than one.

 

sure... I'm on my 4th Prius so I'm well aware of pad length (I've actually had pads out-last the bearings on a car (120K miles)). But that's not the point... the point is that they had a failure covered under warranty and they went and lessened the life of a disposable part as part of the fix without even asking if that was ok. Kind of a sleazy move. If it was bad enough to warrant resurfacing something tells me they removed a decent amount. And I hope that they used a purpose built machine to do it... if they sanded it by hand then there's no way in hell you're going to get the angle correct and until you wear the pad flat you're going to get less than 100% contact and less than 100% breaking force.

 

I think when they sand pad faces they're removing next-to-nil, just doing a quick roughening.

 

You raise valid points if in fact they did substantially shorten the life of the pads through sloppy or over-aggressive sanding, or created future problems through incompetent work. But it's also possible that they removed very little material and did an overall good job. We just don't know. We also don't know if sanding the brakes was necessary, good chance it wasn't, but it sounds like the mechanic tried less invasive solutions first, and when that didn't fix it they spent time doing several brake noise mitigation steps, one or more of which appears to have fixed the problem. Yeah I guess they could have done each of the noise mitigation steps one at a time and test drove the car after each one, but they were chasing an elusive problem. And yes they could have added additional time informing the OP that they were going to sand the brakes and giving them an estimate of how many miles of reduced pad life that would result in. But if it was me I'd probably be like the OP and be happy with the service that they received, but each person has their own criteria which is how it should be.

 

I personally would have let it go as well... but it would have niggled for a bit though...