Any one had voltage regulator problems before? Some of the 4x4 forums said they've had similar problems. When the electrical system is under a load (lights on) the relays start getting hot and the battery drains. Just put a new alternator on and ordered a new regulator but of course my luck it was wrong and my truck has the less common type which is harder to find and more expensive.

 

Thought it was inside the alternator??
I just lost mine (internal) & in turn lost my air controller (ECU).
I went with a GM si12 unit. Had to do some modifying,see my post & photo's!