Hello 6.5 diesel community, I have a 1995 6.5 diesel k2500 suburban vin number F, 4x4 automatic. I'm having trouble getting it started in hot weather. Wondering if I can get some ideas and feedback it would be greatly appreciated as I had 2 suburbans that did this. Before this it ran almost perfect, no knocking or vibrations. Just some bucking and surging I assume from the injection pump. PMD is brand new with new FSD cooler mounted on the bumper. I have 2 good and healthy batteries putting out 12.7 volts and a healthy starter. In cooler weather (about 5 to 25 degrees Celsius) it runs and starts fine. In hotter weather I cant get it to start up as nice as it usually would. Brand new Bosch glow plugs, light comes on for a good amount of time the GP controller works fine. But when I try to start it, the starter dies down and the cables get hot and it slowly revives itself after about 20 seconds of cranking. Even flashing the glow plugs multiple times. I'm assuming the prolonged starting is due to the injection pump. But why would it be draining the batteries? I've come to the point now where it just wont start for the life of it. Everytime I turned the key the cranking would get slower and slower until it essentially seized up. Batteries were a bit low, charged them up to full and tried again and it's an extremely slow start with lots of draw at the starter. I've had this on 2 trucks but I cant tell what the problem is. Spun bearing? Something is siezed? The pulley system is good and doesnt slip and isnt seized at all. Alternator is good. Please help.