If you are changing every 3K miles then dino is OK. Synthetic would become expensive as diesel takes more oil then gasser. I used to use any cheap oil and change it every 3K but now I use C rated oil from Costco. That was before I realized diesel car needs to use C rated oil as I have never driven one before. I drove the 300D & 300SDL for over 20K before I read it from this forum. It does not seem to have done any damage to the cars. Sometimes I question whether C rated is absolutely necessary if oil change is done every 3K. Any oil is better than no oil, I suppose.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.