The 145 amp alternator can't hurt but they seem to have the exact same voltage drop at idle with the fans on high as the conversions such as ours that are still using the stock 105 amp alternator. Control the fans right and bump the idle speed up a hair and you will be good either way you go.

 

Just go online to oreilly's and search around and you will find 105 and 135-145 amp alts. You might have to search a tahoe suburban or 3/4 ton to find one but it will bolt right up as long as the connector is the same. Also they have different belts for the 105 and 135 amp alts. I put on a 135 amp alternator a few weeks ago because my 105 went crap and the 105 amp/stock belt would fit, but when i bought new belts a couple days ago they asked which i wanted and went ahead and got the longer one for the 135.

 

I was using Goodyear Gatorback stock belt for the 105amp, which for some reason works on 130amp alt i have, and when i purchased a replacement stock gatorback belt, the damn thing wont fit! It's 1/2inch too short. I know the old stock belt is worn and stretch long before i replaced the 105amp alt to the 130amp. So now, its either send the stock 105amp belt back and get the longer belt or i have a slightly smaller Alt pulley by March to swap out my stock pulley on my 130amp.

 

GM# pn# for the 130amp is 10464443 AC Delco 321-1803 sorry for the late reply on this, some issues came up, but this should be from either 04 or o5 Z-71 Tahoe or maybe fully loaded Sub. I hope this helps.

 

I've been running 05 efans since pretty much 05, and my lights dim/gauge dips when the fans hit on high, doesn't happen when they come on low. I have a 145amp alternator from an 03 Denali IIRC, and have upgraded the B+ fusible link from the red box to the alternator, which helps, but doesn't cure the problem.

BTW, if you decide to do the "Big 3" upgrade, be sure to put a fuse inline to the B+ terminal of the alternator, or you run the possibility of burning your whip to the ground

 

B+ terminal?