Do I need a replacement?

[Pink∆Floyd]

Ok,I've noticed that my iPhone 3GS' battery has been draining super fast. It isn't jailbroken, it has an AT&T 3G sim card on it. I woke up today at 7am and right now at 4pm.
It went from fully charged to 40 percent. If i go to the apple store and ask for a replacement, will i get a new iPhone 3gs because right now mine's in MINT condition?

 

[GimmeSlack12]

You're saying over the course of 7am to 4pm your battery went from 100% to 40%? Unless you haven't used the phone today then I'd say you have a normal iPhone.

 

[-aggie-]

If they find a problem with your battery, you'll get a refurb.

However, you haven't provided enough info to determine if there is an issue. What's your usage? What's on?

 

[Pink∆Floyd]

I didn't even use my iPhone for all of this time, it was in sleep mode the whole time...
nothing was running...

 

[nagromme]

It does sound like you may have an issue in need of either a full restore (software) or replacement (hardware). If you get a replacement, it may be a refurb, but those are like new (and have been tested more heavily than a new phone, in theory). Refurbs can just be returned-never-used phones—you won’t get a “used” phone. I’ve gotten a couple replacements, and if they were refurbs you would NEVER know it.

One other factor to look into: the battery METER could be miscalibrated, showing 40% even if you really have more than that. Letting the battery run all the way down from full charge to shutdown would re-calibrate the meter and eliminate that possibility.

You're saying over the course of 7am to 4pm your battery went from 100% to 40%? Unless you haven't used the phone today then I'd say you have a normal iPhone.

I go longer than that with occasional use (short calls, short email/web/game sessions) and see almost no drain. Depends on the apps used, of course. I do have all optional stuff (GPS, WiFi) turned on except for BT.

 

[GimmeSlack12]

I go longer than that with occasional use (short calls, short email/web/game sessions) and see almost no drain. Depends on the apps used, of course. I do have all optional stuff (GPS, WiFi) turned on except for BT.

I hear what you're sayin'. I generally get the same battery drain as you are talking about, but somedays I spend more time playing games on my iPhone than normal and the battery can drain down to 40% pretty easily. I was assuming the OP was using his phone in this manner. If this isn't the case then, sure, go have it looked at I guess.