Quote Originally Posted by DieselLSE View Post
If there's a D4 you're interested in, the very first thing to do is an oil pressure test. The old-fashioned way: with a pressure gauge. If it is slightly down on spec, then the bearings will be worn and the motor is on its way to destruction.
My view is that the interval between any oil pressure reduction due to bearing wear and shells grabbing then rotating is extremely short because the bearings do not have a wear layer, instead a thin, hard coating which once breached exposes the soft aluminium backing. If there is any reason to remove the body then remove the engine and replace all bearings with tri-metal versions which have 2 wear layers on top of the aluminium.