Very good advice is to check and be clear how and the distribution of power to the glow plugs and when it should be or more important NOT be energized. A good set sucks a lot of AMPS 80 +/- so it is easy to see the VOLTMETER dip when when they are going hot and or cycling (voltage drop in system wiring)
IMO Ohm them out first and go from there. Anything over 5 Ohms, toss them in the "just in case" spares box. Open ones to the scrap metal bin. If you are going for new change them all at same time and keep fingers crossed. Go to the first statement above and VERIFY the BOX is not "HOT HANGING' Shut it down if OVER 8-10 seconds and start scratching head for serious BOX trouble. Good batteries are a must. Those plugs you listed for sale are good too.
HOW TO:
IN or OUT of truck, ONE at a time.
Using multi-meter, check glow plug internal resistance OHMS. Verify meter is functional correctly FIRST.
Connect one test lead to top terminal and other test lead to threaded area.
Glow plug internal resistance should be 1.5-5.0ohms.
If resistance is not 1.5-5.0 ohms, replace glow plug.
Note: Should be in a range between the others. Say 1.6, 1.7, 1.8, 1.9, 1.8 Matching closely. Odd ball out is 4.6, 2.4, 5.3, 3.1, 1.9 not matched up well BUT ??? workable.
NEW ONES... CHECK BEFORE USING.
No dog in the race link here >
https://www.accuratediesel.com/shop/115.html
Get them while there hot,
CAMO
GOOD LUCK
