Have you gone through the basics?
Load test batteries?
Run about 3/4 gallon of fuel out the drain T, noted flow and looked for crud? Let the fuel sit for 20 minutes or so and look for water bubbles on the bottom. I use a gallon pickle jar.

You tested for power to and from the PMD. I'm guessing you found my December posts on the other forums. Google jrsavoie 94 CK3500

Did you check your grounds?

I do the Allen screw battery bolt upgrade.

I add grounds directly from the battery to various points on the engine and try to solder most connections. I try to use one piece of wire with added eyelets as much as possible.

I add grounds from the battery to the battery box bolt, to the ground on the frame, to the stud with all the ground by the fire wall.

In the cab I add a ground from the blower motor to the dash mount, just a few inches away.

I use #10 wire for most of the grounds. I add a ground to the PMD heat sink - even though I've been told it's unnecessary.

Make sure you have a ground to the injection pump. I have also added a ground there on occasion.

check the oil and coolant levels.

Use lubricity additives as much as possible.

I find &/or fix most of my problems before I get through this check list.

I have fixed problems several times just by running fuel out the T drain.

I also hot wire the lift pump while doing diagnostics. It will 0ften purge air out of the system.

These vehicles will not start if they are not turning over fast enough.

New parts do not mean good parts

When you run fuel out the drain T, note the flow rate

 

Yea most basics covered. Brand new batteries charge after everyday of working on truck. New starter going.on tomorrow. As you mention the t valve it doesn't seem to be a great flow almost a drip. I too jump out lift pump at oil pressure switch pump runs and fills filter housing. Will it come out t valve with just lift pump running or must engine be cranking? I got very little out t with just lift pump running. Checked all connections and grounds. Tested all glows with test light also verified 12 volts at glows when active. Could all injectors be stopped up? Not likely. could it be the injection pump? I have fuel at all lines but who knows may not be enough pressure to open injector. Will try and find new lift pump in stock somewhere tomorrow and fuel filter also. I also have suction side of lift pump directly in fresh diesel can. Previous northern truck lines are rusty. Thanks again for all the help. Will try post some more tomorrow sometime.