I have a 1996, always maintained very well Chevy Silverado, it has the 5.0 liter engine. The issue is I have been having problems with it hard starting. The temperaturte outside has nothing to do with it. As long as I start it every day its O.K. but it just takes to many cranks for it to turn over. Could it be the fuel pump or possibly a filter being clogged? I spray in a little bit of starter fluid and it starts up. Let the truck sit for a few days and its very hard to start.

 

Put a fuel pressure gauge on it to see what its doing. Sounds like it could be the pump

 

does yours have a throttle body,if so my 5.7 liter does the same it is very easy to start first try the any time after that it cranks and cranks before it hits...i put a fuel pressure regulator on it and i can turn on the switch and it builds up pressure then when the pump kicks off it looses it . i have herd from a few people it is the spyder injectors. under the throttle body...

 

thats the problem with mine also... When I turn the key on and let it sit for a minute then start it, it usually will start pretty quick

 

The check valve in your fuel pump assembly is bad. It is letting the fuel bleed back into the tank. I added an inline check valve in my fuel line and solved the problem.