As a truck driver, oil is very important. I would not recommend Rotella, as I have seen the inside of an engine that was regularly serviced with Rotella. This includes the Pilot Brand, which is Rotella. The engine was filthy!!! Mobil Delvac is an excellent choice, and got an extra 60K out of my bearings which were damaged by a diesel bat, as is Delo 400, which is the thickest of the oils (helps keep my oil pressure up on my Cummins n-14 Engine). Castrol has a blend (Castrol Tection) which is well known by mechanics for suspending dirt, which gets trapped by your filters. A good choice for keeping the engine clean. But most important, which ever one you choose, stick with it and change it regularly.

Exactly what I was waiting to hear from another end user, Delvac and Delo HDEO represent the best value in oil today. Delo is ISOSYNTH and performs on level of synthetics and unless one is going to drive in extreme conditions, these two HDEO will serve you well. Both my diesel engines are pristinely clean, one after 178000 miles and other after 110,000 miles, thats how good these two oils are. My compression is as good as it was when new, cam wear etc. is minimal. I have driven Delo and Delvac through 55C summers of Rajasthan in India and driven my 300TD across the Arizona desert. Delo didn't break a sweat and neither does Delvac. Countless UOAs done on these two oils reveal what we users know, there is nothing that comes close to these two oils when it comes to keeping engine clean and preventing wear and tear. Btw, I have used Tection and even though it kept the engine clean as Delo and Delvac does, it couldn't take the hot North Indian summer and thinned out quickly unlike Delo and Delvac.

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99 Gurkha with OM616 IDI turbo

2015 Gurkha with OM616 DI turbo

2014 Rexton W with OM612 VGT

I have no clue, because I just purchased my first Mercedes diesel the other day. All I know is that the PO used Rotella 15w-40 for years in the 84' 190D. Here is a photo of what it looks like inside of the valve cover. Not sure if you can tell, but it looks like new in there.

I was not sure if this is how all diesels typically look or not. I have only owned gas cars before and I can say that I have seen some pretty nasty looking gunk in there.

Not on this car though... this is what it looks like... maybe thats typical? This car has 157K miles.

I found these guys:
http://www.zddplus.com/
and may use this as an additive to normal 5w40 motor oil for winter use (with 15w40 Rotella T for summer)

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1982 240D automatic
Odometer quit at 307K...about 325K now

This is my OM616 turbo on Delo and Delvac at 108000 miles.

Attached Thumbnails

 

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99 Gurkha with OM616 IDI turbo

2015 Gurkha with OM616 DI turbo

2014 Rexton W with OM612 VGT