If your truck is sitting outside for 6 hours, and it's 20 degrees out, Is it normal for it to sound like the alternator isnt getting enough juice?It sounds like it's just barley getting enough to start the engine, and im afraid if it gets any colder, that it might not start...could this be a sign of an old battery? or what? I have a '99 1500 w/ a 5.9, and it sounds like it's just barley gunna start...but in warmer weather it starts like a champ.

 

battery might be going bad.. if you get a new one make sure you get a cold start battery that is specially made for cold temps.. i live in western ny and we just got blasted with our first snow for the season.. and if you look into getting a new alternator.. see about getting the one for the sport offraod models.. they are made to run higher outputs.. like 130 amps.. witch is way higher than the regular one.

 

Its normal at -40 but not at 20 above which isn't very cold. Optima. They may cost a bit more, but they are the best.

 

Check your alternator with a voltmeter to see if it's charging properly. It could be that it's not fully re-charging the batter. If you do not feel comfortable doing that, a place like Autozone or Checker (or whatever the auto parts store in your area is) can do it for you.

If the alternator is functioning properly, then it is most likely a weak battery as mentioned above.

 

I would take bets that the battery starting to go bad. If it is the original battery and a 99 truck then the battery is about 7 years old and that is some pretty good life out of a battery. Cold weather is a batteries worst enemy.

 

Ya, sounds like the battery to me too. If you replace it, get one with good cold cranking amps.

 

It could be the battery, but he didn't state whether or not it's the original battery that came with the truck. I suggested testing the alternator, because I've seen people all too often with problems similar to this, replace batteries in the winter only to have them fail on them a week or two or three down the road when the alternator was the true culprit.

It could very well just be the battery, but when it comes to winter starting it's a good idea to check everything out. It's better to be safe than to get stuck somewhere in the cold and be sorry.

Also...what Silver_Dodge said! If you do get a battery, make sure it has a high CCA (Cold-Cranking Amp) rating. 700+ is a good rating, especially for a truck. I have a 1000CA/850CCA battery in my V10. It was in my 4cyl K-Car before I sent it off to the scrap yard. [8D]