A Glow Plug Longevity Data Point
 

Glow plugs on my 602 were replaced 65k miles and seven years ago. Car mostly driven around town (in other words, lots of short trips thus lots of starting). Just had first one go bad. They're Bosch.

Wonder if I can get through a New England winter on four plugs.

is it easy or "remove the manifold" one?
either way I would replace it...


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In general Glow Plug life depends on Fuel burning in the Prechamber happening when and how it is supposed to and if the Carbon was Reamed or otherwise cleaned out of the GP Holes.

After that it is the quality of the GPs themselves.

65k is longer than I let my spark plugs go (yeah yeah they're no the same...) I'd say you did pretty good. With a block heater you might still be able to start...

I replaced the glow plugs (strictly as a preventative measure) on my OM617 after 25 years and 150k miles. They were all still working and showed few physical signs of distress.

Speaking of spark plugs.....our 02 Honda Odyssey has 158k on original plugs.

Crazy! I melted 1 (of 8 on a 4cyl) after 20-something....she was runnin' lean it appears

04 Diesel
 

Replaced his ,with the Intake ON.
(1/4 inch tool MAGIC and Patience)

Only UpGrade is Bosch's "Chromium" Plugs [Only available in the EU]

http://www.peachparts.com/shopforum/diesel-discussion/227819-bosch-duraterm-chromium-glowplugs-3year-warranty.html

Bosch Duraterm Chromium Glowplugs - MBClub UK - Bringing together Mercedes Enthusiasts

On my 91, replaced four out of the five at 81k miles in 2009....first one of those just went out at 113k miles. Bosch.

What's the big deal with pulling the intake? Just replace them all for a piece of mind. It's one of the first things I do with a "new to me" diesel Merc.

Our 03 sprinter has the original glow plugs and no issues with them at 185K miles.

My 93 190E 2.6 parts car has original spark plugs, distributor, and wires and still runs with 210K miles, although poorly because one of the injectors leaks.