I've been running the '85-newer style glow controller on my 6.2L along with a resistor to increase the glow times (for use with the AC 60G glow plugs) and all has been great. In warmer weather when it's over 95 degrees outside or so, sometimes the glow plugs do not cycle for a warm restart and that sometimes causes harder starts. Anyone have an idea why the plugs might not be cycling in hot weather? I'm not running one of those inhibit switches that prevent the glow plugs from cycling when the coolant temp is over 125. Could it be a failing controller?