chevythunder

hey guys, I have a 04 tahoe and the original battery took a crap, so I put in a optima today and put a tester on it to see if there was a drain that killed the original, it would read 12.20 for a couple of seconds drop real quick to about 12.03 then go back up to 12.20. It keeps doing it over and over again.I'm not sure if anything like this is normal on these newer cars.thanks

n1wvet

This doesn't sound wrong. It sounds like something is cycling or flashing. If you really want to check what's going on,hook up an in line ammeter to the +12v line andmeasurethe current. I'veseen 50 to 100 milliamps of drain even when the Tahoe is off. Lots of things have a slight drian on the battery like radio settings, security alarms, PCM, etc...Don't start the vehicle with the ammeter in line. It will fry.

Three years is about right for abattery replacement. The Optima should last a lot longer.

chevythunder

today I lost .50 volts in a 8 1/2 hour period, I'm just thinking that if it sits for a couple of days it might not have enough left in it to start. I'll give that a try and see what happens. thanks a bunch