car starts fine when outside temp warm but barely turns over when its < 40 deg

Corroded cable connections are one possibility. Despite what Sears said, the battery may nont be up to snuff. You can't always depend upon battery tests, even by experts, and the dobbers at Sears may not fit that category. Third, a 'dragging' starter can drive you nuts. Often caused by worn bushings, the symptoms mimic low battery almost perfectly. The cure is usually to replace the bushings, clean up the commutator, etc or replace the starter.

Corroded cable connections are one possibility. Despite what Sears said, the battery may nont be up to snuff. You can't always depend upon battery tests, even by experts, and the dobbers at Sears may not fit that category. Third, a 'dragging' starter can drive you nuts. Often caused by worn bushings, the symptoms mimic low battery almost perfectly. The cure is usually to replace the bushings, clean up the commutator, etc or replace the starter.

Approximately 9/29/03 21:04, Mike Salazar uttered for posterity:

Two things:

Check your battery and battery wiring for corrosion and tightness. Not only does the battery put out less power at colder temperatures, the engine takes more power to turn over and/or start.

Also check your oil, you should be using a winter graded multigrade as noted in your owner's manual. If you have a can of 30 or 20 weight normal oil, stick it in the freezer and see how it doesn't pour so good anymore.

I had a similar problem with a Saab 900S a few years back. Dreaded every winter because i knew i would need one or two jumps over the course of the season. Car ran great spring to fall, but in the winter it would always die two or three times. Battery checked out OK, but i replaced it anyway. Still ran into the same problem.

The problem went away with my first jumpless winter, when i had to replace the alternator (the previous summer). I'm not a car guru, so i'll let you make your own guesses :)

-Brenden