I'd expect to see at least 50 volts in the battery when it's fully charged up.
Have you checked for any dead cell's?
You say the battery is recent / lightly used, Is it the correct range AH battery for the truck & is the battery parameter set correctly?
This truck is just a BT Reflex RR B with Toyota stickers on.
This is ONLY to be used to report flooding, spam, advertising and problematic (harassing, abusive or crude) posts.