THE connecting rods were modified durning the 1994 model year & installed on engine number 603.971-12-013644 & later.
IF you need to replace a rod on earlier engine numbers including the OM603.970 engine ALL of the rods "must" be replaced as a complete set.
THERE have been 4 different part number changes on these rods!!
WE (dealer) have replaced at least 10 sets!

THERE are still many(most) engines with original rods that haven't had ANY problems!!

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