I have an 87 300sdl that won't go above 20 mph. I've changed the fuel filters and checked the alda. A diesel mechanic said it was probably the trap oxidizer. Will mercedes still stand behind this after 21 years? I understand there was a recall or an open campaine on these. Is there any documents to support me on this when I call the dealer? I have a feeling they won't want to cooperate.

Mike