Engine Performance problem
2000 Chevy Silverado V8 Two Wheel Drive Automatic 72500 miles
Truck is 1 ton dually. 454 v8 gas. When starting first tume in morning, start immediately, after driving for 30 minutes, very hard to start. Must crank several times, to start, after starting runs fine. No missing or rough idle. Replaced air filter. Fuel filter replace at 50,000 miles. What could cause this problem?