Originally Posted by jake12tech

No. I doubt an OBD2 will tell you a glow plug is bad. I never even tried because I tested the plugs myself always. My theory would be that the OBD2 scanner would only work if it is throwing a check engine code with the CEL light. Not the glow plug light on the dash.

Check your alignment. Being it was driven a lot constantly it could be out of alignment. BTW if you do get an alignment, take it to the dealer. They have the correct equipment and knowledge of how to get it spot on. I am privileged with a great break at the dealer because my old man was a tech there for 3 decades, but if I don't do my own alignment at the time I still take it there knowing I won't have to return or have a mistake made.

My best advice regarding the suspension is:
Get it on a lift and inspect it yourself eye to eye. Get under it because I can tell you my diesel doesn't ride like the W210 suspension I rebuilt awhile ago on a 99 E320. I have 160K miles on the clock so once 175K rolls around I will do a front end rebuild.