I have a 89 F350 with the 7.3 idi in it. Truck has been running great no problems at all. Went out to start the yesterday and it it fired up ran for about 15sec and died and will not start back. I tried a shot of ether(which i have never had to do) and still nothing. Glow plugs are new and the gp controller is new i did verify the gp and gp controller are working it will spin over good but will not start. No smoke out the tail pipe
Have you checked your fuel level? Look for leaks in the return lines/caps on the injectors, could be a drainback issue. Lift pump might have went, check your oil level to make sure your crankcase isn't full of diesel. But first make sure you have diesel in your tanks, if you don't, fill 'er up and be prepared to crank it over for a while.
like wil ziggy said check for air, and if not, try a fuel filter, i know my 94 is a bear to start if the filter is clogged, also you said the rear tank is full, did you just fill it up? was it sitting in there for a while?