Originally Posted by chuyrobles

It seems counter-intuitive to me to replace the starter if voltage to it is low. At this stage, the starter would be the last suspect. The starter does not 'put out' voltage, it takes it. So a low reading at the main starter cable connection indicates there could be a connection problem there or at the battery post. If I recall correctly, there is a pos battery cable directly connecting the battery and the starter. The solenoid cable runs in from the fuse box. The ground cable goes from neg battery to a transmission ground point near the starter. A smaller neg cable goes from battery post down to a chassis point below the battery tray. All these points need to be removed, inspected, cleaned and layered with dielectric grease or a battery chemical spray to prevent rust.

I haven't read that the battery was load-tested. A bad battery can still put out normal voltage, but if the internal plates are fried, it will not sustain that voltage under load.

I hope you figure it out.