Hello I have a 02 Silverado 2500hd 6.0 .I'm getting one click and no start. I charged battery,put new starter in and makes same exact sound.one click. Relay good. Please any tips on what to test next? Thank you

 

Can you do this,
Turn the headlamps on and attempt to start the engine. What do the headlamps do, go dim, stay the same?
If the headlamps go dim, I would suspect a problem with the battery cables. or a seized engine.
Can you turn the engine over by hand using either the alternator pulley or anyone that is connected to the belt that is easy to reach?
There may be more to this than we presently know, is there?

 

Thank you for your time it's much appreciated. The lights did not dim and I just tried turning crankshaft pulley and couldnt move it at all by hand,will try with leverage tomorrow, Trucks been sitting,it's a plow truck.