The S10's alternator has been acting up so I'm taking the 105A alternator out of the Silverado to put in it. I'm putting a 145A alternator (AD244) from a NBS truck in my '98 K1500 Silverado. Alternator When I was on AutoZone's site, I selected an '03 2500HD 6.0L. I think, but am not sure, that this can be found in any '03-'06 Silverado, 1500 or 2500, however it is an option (in case anyone is looking in a junkyard for one). The serpentine belt I picked up a belt for the GMT-400 with the factory 140A alternator. Do not get one for a NBS truck with the 145A; that belt is 92.91in VS the 96.85in that is needed. In case anyone is wondering, a 140A for a GMT-400 will not directly plug into a GMT-400 / OBS that has a 105A. The electrical connector is different. (I bought the 140A first; doesn't work) Parts list alternator = Duralast Gold DLG-1923-16-4 @ AutoZone for $195 belt = Duralast 968K6 @ AutoZone for $29 FYI The alternator needed to be specially ordered in my case. So I had to pay for it in advance. Just in case you are planning on doing this yourself and want to get it done on a specific day. Hopefully I'll have this in by the weekend to let you know how it fits and works.