Hi.
I have a 2009 is 220d with 110,000 miles. If I accelerate hard in first and second gear, I get a knocking noise from the rear. This does not happen if I accelerate while I am driving at speed only when I am going slow.
Car just had a new dpf fitted by Lexus as well as a service but there was no noise before they got their hands on it. Local mechanic went for a spin and could hear it but was surprised that it didn't happen at speed. Car was up on his ramp and he couldn't find anything loose that could cause it.
Any ideas??