I just spent the whole day going through my electrical system. Checked all cables to and from batteries, starter, etc. Scuffed everything well to ensure good contact. Batteries are new and hold charge. Alternator appears to be working as it should. Pulled the starter (again) and this time took apart the whole thing for a serious cleaning. There was A LOT of crud built up inside the housing....spent a good 2 hours cleaning everything. Put it all back together and into the truck. The starter definitely cranks faster than before, which is good, but for some reason it still takes longer to fire. I am completely at a loss for what to try next. My other list of possibilities are;
1. Alternator - but wouldn't the batteries drain as I'm driving?
2. Fuel pump - but wouldn't I notice power loss, stalls, etc?
3. Fuel injectors - but there is no white smoke, power loss, or misfires
Also, I just noticed that my stock batteries were rated at 750 cca, but the replacements are 700 cca. Could a difference of 50 actually be enough to impact the starting?
My other, and maybe last, idea is the computer. Is is possible I need a "reflash" or whatever the dealer calls it in order to charge me a lot of money?
On the bright side, at least the changes I've made thus far have helped...so at least I have a little time to debug the problem. Any help is appreciated.