Sir, I have a 2014 VW Passat / auto transmission / 150,000.km which I bought from a private party about one and half years ago. 

1. The vehicle is having brake noise / squeal for the past couple of months only when applying the brakes. It sounds like a sharp squeal. I thought the brake pads were worn out, but there is about half the pads remaining. As per the mechanic recommendation I had the brake discs polished and the sound went away. After about running for a month the brakes start to squeal again. The mechanic said it could be because of bad brake pads and now recommends to change all pads. Could it be anything else wrong making the sound.

2. The vehicle jerk / shake when shifting gears especially in the low gears while accelerating. It feels like someone hit the vehicle in the back. The mechanic said it is due to bad engine mounting and I got it replaced. The jerk has reduced a lot but not completely gone. The mechanic said he can try replacing the transmission mounting also. It cost a descent amount of money to have the engine mount replaced and I was thinking if I can postpone replacing the transmission mounting. Could it be any other causes for the jerk and would you recommend replacing the transmission mounting.

Thanks for your input.