GM-GMC: truck wont start, switch circuit, battery cable

Question
My truck wont start. Its a 98 sierra 2500 diesel 6.5 turbo. When I try to crank it over it just clicks. I've had the batteries checked and they are ok. I replaced the starter and it does the same thing. Any ideas?

Answer
well the top 6 corrections for your problem is:

1 Inspect  Battery  Insufficient battery voltage/amperage  (Which youve already done)

2 Inspect  Battery Cable  Corroded, broken or poorly connected battery cable.  

3 Inspect  Battery Cranking Amps  Insufficient battery voltage may require recharging or replacement  

4 Inspect  . Obsolete116  Damaged or faulty charging relay  

5 Inspect  Solenoid Switch  Damaged or faulty solenoid switch or solenoid switch circuit.  

6 Inspect  Starter  Damaged, worn, defective, or faulty starter or starter related circuit.  (which youve already replaced)

good luck

Bruce