Hi Steve, When I was thinking of replacing all my glow plugs, what I found was crazy. The person who owned the truck before I did must have had an issue with glow plug #6 (a pain to get at and could not remove it), what they did was to detach the connector and take a new glow plug , zip tie it...
2015 194,000+ . Throws codes all the time, but nothing serous. bought it used with 185K on the clock, but it looks like it was a highway only vehicle, very clean. Hope to keep it for another 100K+