Ok, so some back story...Dec '07 we are on the last half of our 600 mile two day Christmas obligations when the alternator goes out on the truck, it is dark, snowing and cold.
We make it home and two days later a brand new rebuilt lifetime warrenty alternator from AutoZone has been installed by me.

Dec '08, it has been snowing all day, 8" of new snow last night, another 6" today with high temps in the high teens low twenties.
I am wet, cold, tired and hungry.
It's dark, I am driving home, it is snowing, 10 miles to go on the expressway atthe neck breaking speed of 30 mph.
Tach goes dead, battery light comes on and head lights dim, crap, alternator took a dump.
Turn off all non essentials.
Hang up with wife, call AutoZone, the only alternator they have in stock is 12 miles across town, did I mention it was snowing?
Backed the Volvo out of the garage, pull in the truck, rip out the bad alternator, family and I drive across town, get new alternator, drive back home.
Install new alternator, did I meantion that I am wet and cold? Water from snow melting off the hood of the truck is dripping down the back of my neck...and I love it.
Removing the bad alt while the engine was hot...I love it.
Scraping my knuckles on the radiator as I loosen the serp belt...they bleed...and I love it.
Get the new alt installed, fire her up and put the car back inside and the truck parked back into a snow bank...makes me sad.
Knowing that the truck is up and running and as reliable as ever makes me happy, God I love working on this truck.

Total time to do actual work, 30 min.
Start to finish 3 hours, and no, leaving the battery unhooked for that long will NOT clear your Check Engine Light.

 

Maybe you should have had it UP's to you. I'M Just kidding of course you would have it Fed exed

 

those rebuilt auto zone and advanced auto parts alternators are notorious for going bad. You're lucky you only had to change it out once. Their starters are the same..I use to work at advanced and would see people go through 3 before getting a good one.

 

Sounds to me like you should stay home when it starts snowing in December. Seems like your truck doesn't like it

 

Dropping your battery cable will not clear codes, that is a scanner only.

 

One of the reasons I always order from AB is because I can choose FedEx Home Delivery and get paid to delivery my own package.

I know that rebuilt parts from AutoZOne or some other discount auto parts store are not the best, but the price was right and a lifetime warrenty. A actual LR alternator is $600.

I know that unhooking the battery wont clear any CEL codes, but there was a rumor that it would, and since you have to unhook the battery to replace the alternator...I thought that I would debunk the rumor.