Re: 90 K2500 Hot starts pulls battery down to 8 volts?
I've put a NAPA starter on a 454 in a C2500 and it works great, after it gets hot it is slow cranking, no heat shield though. I dunno what Autozone's options are but I work at a Schuck's (same as Checker/Kragen) and we have 3 different grades of alternators/starters we sell.
Cheapest = Remanufactured unit, the maximum amount of parts are reused, they've done the bare minimum on remanufacturing to make it work. 3 month warranty.
Middle = Remanufactured unit, only the housing is used, all of the internal parts are brand new, as well as the solenoid (if it's a starter). Lifetime warranty, I think a 24month Roadside Assistance Guarantee.
Top Shelf = Brand New...everything, no reused parts. Lifetime Warranty, I think a 36month Roadside Assistance Guarantee.
Don't quote me on the roadside guarantees, I might be wrong; but I'm right on the warranty portion.