Does anyone out there on the forum know of the easiest way to change 2 lifters on the right bank of the E-420 engine??? Do I need any special tools also do I have to remove the timing chain on this vehicle. ??? Do the cams have to be removed??? For some reason or another things are really starting to go haywire on this beautiful automobile. I want to thank everyone for all of their imput on the other problem, that has solved itself somehow. By the way, I checked all of the oil tubes on the right bank and all are fine, found one lifter making noise, cam lobe looked good?? I also purchased new o rings from thedealer for the oil tubes on the right bank. Just trying to put everything in prospective for everyone. I have tried Marvel mystery oil, STP worked for one day kept it quiet and has started making noise again??? Any illustrations or pictures would also be of great help to me on replacing the lifters. Big Ben