So in mid December I bought 8 new glow plugs, after testing the ones in the truck only 3 were still operating...... No wounder right. Do not knowing any better I bought 8 autolites. PLEASE don't buy autolites. I had 2 go out in 2 months. So after some research most people have bad luck with them. Saying the tips can swell yada yada. Well after reading that I'm scared out of my mind about havin to tear into the head... So I went and bought some Bosch glow plugs yesterday and spent the evening replacing them for the second time this winter. I have to admit I'm gettin more efficient doing this project. I've had troubles all winter with my 7.3 and most times if not plugged in overnight I don't even bother trying to get it Started till its warm. I have the stancor relay new plug and also I switched to Rotella 5w40 synthetic. It was actually on sale at the parts store. So I'll be curious to see how the cold weather, now that it's almost spring, does for me now! I work 11 days startin early in the morning and by 6 in the evening my truck would be hard starting. This was December January February kinda thing but still can happen still gettin into the teen where I live. I know there is plenty of write ups on here about similar issues. But the more the better I rekon.