THERE really isn't any recommended replacement mileage for ANY timing chain. Inspection of chain stretch VS correct cam timing "should" be done any time that the valve cover is removed.
IE; every 60k to 75K miles.
For that diesel engine you NEED a oil rated SH-SJ & CF-4(diesel rating) or higher!
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)