Originally Posted by
chturner
Advance is also in the business to sell batteries. Just trying to make sure it is absolutely the battery and not a starter or alternator problem
I feel your pain, bud.
It may well show 12.6 at rest and 14.6 when charging but when it drops to 8 (slow cranking) it will confuse all the systems in the car.
Replace it. Shop around, but replace it.