Running on 1 battery?

[TANPOWERSMOKER]

Ok I was working on my truck today and noticed them battery terminals
Were lose 'so for the he'll of it I disconnected the driver side batt and fired the truck. Then disconnected the pass battery and tried to start with the driver battery and nothing except dim lights and faint beep of door bell. How can I test if the battery is not getting juice from alternator or what's causing it to be dead?

[jesilvas]

Well with them hooked up you can test the battery on the terminal itself, not the terminal clamp.
If the volts are different between the clamp and terminal, then it's not making a good connection.
Chances are you have a bad battery.
Load test it separate of the other one.

[TANPOWERSMOKER]

What's the best way to load test it?
And if one battery is dead can I buy just one or should i get two new ones?

[jesilvas]

It's better to get both because the 'good' one could be weakened by the bad one.
Auto stores have load testers but they need to be heavy duty ones.
Test them individually.

[ryandamo]

if you have a battery tester,(harbor freight sells them for like 30 bucks) hook the driver battery up then hook the tester up to the starter where the line attaches, then test battery, that how you know if your cable is shot, never rule that out.

[TANPOWERSMOKER]

Who sells factory replacement battery cables?

[TANPOWERSMOKER]

Up date
The suspected bad batt tested under load at 7v. So I swaped it for a new one hope that helps

[elrojo63]

did you get two batteries?

[Turbo_pace]

I had the same problem, mine cranked kinda slow so I replaced all the battery terminals and come to find out I was only cranking on the driver side battery, after I soldered on new terminals the truck cranks twice as fast and starts easier.

[zROCK]

replace them in pairs... and stay away from napa batteries im replacing mine after less than 3 years