Really good video of an OM642 teardown (ML350)
Super Member
Joined: Jun 2022
Posts: 739
Likes: 328
From: WA State, USA
2014 Cummins, 2014 E250 Bluetec
So - from your own experience the engine is a turd because you've had to fork out money to replace the oil cooler seals (more than once), but you don't know how much they cost? 
If you decide to do the job right and replace all 28 gaskets and seals with OEM parts, the kit is about $150. The oil cooler Viton seals themselves are about $5.
If you are getting near the 240,000 km mark and/or also want to proactively replace the PCV valve, swirl flap actuator (motor), additional gaskets, various tubes, hoses, brackets, bolts and everything else that may be getting there mileage-wise, the parts tally is about $600.
It's a full weekend job but nothing that requires anything other than a copy of WIS, a socket set and a basic tool kit. If you're paying someone to do it, it is probably 16 hours or so.
If you decide to do the job right and replace all 28 gaskets and seals with OEM parts, the kit is about $150. The oil cooler Viton seals themselves are about $5.
If you are getting near the 240,000 km mark and/or also want to proactively replace the PCV valve, swirl flap actuator (motor), additional gaskets, various tubes, hoses, brackets, bolts and everything else that may be getting there mileage-wise, the parts tally is about $600.
It's a full weekend job but nothing that requires anything other than a copy of WIS, a socket set and a basic tool kit. If you're paying someone to do it, it is probably 16 hours or so.
MBWorld Fanatic!
Joined: May 2017
Posts: 1,234
Likes: 153
From: Montreal/Cape Coral FL
2012 X6 35i Sport, 2013 ML 350 BT, 2019 4Runner TRD Pro, 2020 CRV-AWD
Member
Joined: Oct 2011
Posts: 105
Likes: 39
From: SC
2015 GL350, 2013 GL350, 2002 ML320, 1983 E300TD-D
Personally I like my GL350 with the OM642. Yeah I have hade to replace the cooler seals, de-carbon the ports and manifold while they were off but other than that it has been trouble free. I do 5K OCI with Rotella T6 5W-40, run a Provent 200 catch can on it that collects 4-5oz. of blow-by oil every 1,500 miles or so and that's it for the engine. That engine idles and runs smoother than my wife's GL450 (which we ditched due to cylinder scoring issues, M278 POS).....
