My trucks rpm's dip down and battery voltage at the same time every 5 seconds or so. What's that about? 95 ext can v8 2wd auto w/od

 

A/C on?

 

Yes, but it does it with it off as well

 

Have your battery and alternator load tested, sounds like one of them could be getting bad, check cables and connections too, clean them up.

 

Alt going out...batt don't have anything to do with the truck when its running. Batt is used to start the truck and then the truck runs on the Alt after that. You sure the surge is not when the A/C clutch engages ??

 

Bad regulator?

 

Truck runs off the battery and the alternator keeps the battery charged.

 

Say what ?? Lol

In that case I dare you to unhook your battery while the truck is running, see how long it runs

 

It completes the circuit ,,,

 

Yes the battery completes the circuit, it will stall if you unplug it. But the truck does not run from the alternator. Its job is to maintain the battery, all systems run from the battery.

Thats why if your alternator were to die on you while driving, you can get a little further running on your battery. Done that before