My partner and I have 2015 diesels which are identical apart from mine being a grey SE and hers is a silver SE Nav. Her car experiences a vibration at around 60mph, which drops away if you accelerate through it. First thoughts would be wheel balance, but I swapped over wheels between the cars and I didn't get any vibration with her wheels on my car, and the vibration on her car remains with my wheels on. I fitted new front pads 6 months ago but didn't touch the discs as they still had plenty of life in them. If I drive to the speed where the vibration starts, then drop the car into neutral, the vibration disappears, which makes me think it's engine related. The vibration only started a couple of months ago.
Has anyone experienced anything similar, or has suggestions as to what I should look at?