Truck having starting problems, slow motor turn over put a new set of 875cca batts. in not fixed, alt would not charge thats fixed now and the starter gave up put a new one in. Now back to slow start problem again. Truck wont start if it's counting on just the batts. But if the batt. charge on and hooked up and on it starts fine. The batt testing shows 12.5 volts, load test shows good, jumps back to 12.5 volt. Thinking the cca is off but can not test by my self so any other thoughts?? and has a new HPOP too.