Two problems related to engine knocking noise have been reported for the 2011 BMW 535. The most recently reported issues are listed below.
2011 535xi with 95,000 miles was serviced and passed all inspections, less than 700 miles later engine starts making a knocking sound while driving. Immediately stopped and towed to dealer where they found metallic shavings in oil filter. Said engine needed to be replaced at a cost of $36,591 but offered no cause for the failure.
I was driving back to dallas ,TX. On I 20 on March 22 when I heard a noise . The sound became louder and I came to a stop and to see if I could figure out what was going on but it had gotten dark so I continue on until I got home and check under the hood. The car was making a loud knocking sound. On Monday I took the car to a certified BMW mechanic and 3 days later he informed me that the engine was going to have to be replaced. The car has only 68 k miles on.