I am no mechanic but feel that I am so inclined!

Have owned a number of Diesels including my third MB diesel.
Unlike a spark plug the glow plug is functional only in the start process and therefore they should not be worn on a 99 unless there is something burning off the elements. In the name of preventive maint it may be justifiable but not for a cool G.

Are you in a very cold clime or do you start/restart the engine very very often and have near 100000 or more miles on the car?

If the engine is out etc then the plugs should be replaced at cost and perhaps a cup of joe and crumpets (starbucks+) given that its an MB mech!

I'd get the reco and price in writing and take it up with MB central this kind of dealership gives the brand a baaaad name.

I am still looking for a non dealer option in the Dayton area, any suggestions out there (new to the area).

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