|The following is based on Fallout Tactics and is not canon.|
The nuke carrier is fundamentally the same vehicle as the armored personnel carrier, but instead of hauling armored passengers / cargo compartment, it's hauling a live, nuclear warhead. It can only hold three people. The Warrior uses it to carry a nuke to the door of Vault 0 to blow it open, so the final battle against the Calculator can begin. It has 350 Hit Points.
The nuke carrier appears only in Fallout Tactics.