battery or alternator?

so my truck died today. didnt leave the lights on just died while i was in class. got home after someone jumped me and it died again. got it jumped. while i was driving around after i would flip the headlights on and the radio would cut out and then come back on. then i would turn my fog lights on same thing. at one point it almost killed my truck. battery or alternator? on my scangauge it says my battery is running at 13.5 to 14.2 when its on but once it turns off its completely dead

 

well im gonna go to autozone and get a battery first cus thats the easiest and cheapest to replace

 

Check the battery at like a autozone then if it's good check the alternator.

 

Great minds think alike <3

 

okay. im pretty sure its the battery cus it hasnt been replaced in 3 years

 

r ur battery post's clean, & r u getting a good connection with ur battery terminals?

 

Good point. Clean it up with some baking soda and water

 

they pretty clean. i mean ive seen worse

 

try the old test take the positive terminal off the batterie while the truck is running if i dies the it's the alternator if it runs then its the batterie.

 

black positive red negative right? haha

 

nvm red positive black negative

 

well i talked to one of my mechanic buddy's and he says it the battery because once the trucks running it says 14.2 volts on my gauge

 

^^^ Yup. The scangauge is reading voltage output from the alt. Yours being 13.5 to 14.2 is pretty normal.

Its the Batt.

 

fuck. autozone just raped my wallet. 131 dollars on a new battery because they were out of the cheaper ones

 

Cant do that anymore, not on modern cars and trucks. It will damage the computer.

It doesn't seem like the battery has been fully charged. Bring it to the Advance and have them load-test it.

 

24 group size or 27?

 

I've done it to my truck with no problems...

 

I've seen battery cables so bad with corrosion they swell and break through the insulation, so check that also. But my guess battery

 

there was very little battery corrosion around the terminals and i cleaned it off and jumped it again let it run for awhile and then turned it off. same thing wouldnt start. so got a new battery. no problems so far running like normal

 

So what kind of battery did you get?