Dude, you're having problems starting your diesel in the cold weather of *Texas*? Talk about living up to all of the bad stories people tell about diesels! ("They don't start in the cold")

Something's wrong with your glow plugs or you have REALLY bad compression from bad valve adjustement or bad rings. Non-synthetic oil will not help matters either.

My 85 300TD has been starting flawlessly all winter up here in Wisconsin (down to 10F). I haven't done anything unusual with the fuel and I haven't even looked for the block heater. I'm using Mobil 1, 15W-50.

Just because the light on the dash is working doesn't mean the glow plugs are good...

I don't mean to sound un-sympathetic, but you probably just have marginal glow plugs. A friend of mine just changed the glow plugs on his Rabbit and it's been like night and day how well it starts now!