95 f150, charging system problems.

[hazard]

hey guys i got a 95 f150 with a 302, i noticed the other day while driving the voltage gauge was jumping down out of the normal range then going back to normal and throwing the battery warning light on, so i figured it needed an alternator, went out and bought one today and put it on, same thing going on, so hopefully i can get the parts store goon to take the alternator back and give me my money back. but i still need to figure out whats going on with the truck. anybody have any ideas of what it may be? thanks

[raley's04]

Did you ever find out why it was doing that? I have a 94' and it is doing that.

[hazard]

check your inbox raley's04 i shot you a message.