IMHO pulling bearing caps on the rear cyls is a waste of time. If you have low oil pressure it is a bad pump or too much clearance in the bearings causing leakage faster than the pump can supply oil.

I would replace the oil pump or rebuild itand see what happens, this I believe you can do without removing the engine. Some shavings is normal in oil sludge.

If it is too much clearance, the bearings will all be shot and it is time for a rebuild. No sense fooling around with two bearings, imho.

Also, I would not run it so long on my oil changes even with synthetic. I would also go one grade thicker on viscostiy or even two.

You probably should fire your friend and get a mechanic who has mercedes experience, too.

It may be a beater to you but these cars are expensive to repair, and most likely some type of neglect has put it in this shape.

With decent care, the bottom end on those v8s are about impossible to wear out. Cam chain guides are another matter. They require preventative replacement at (mileage varies on the recommendation) maybe 120 to 180K miles.

Tom W

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.