Dang.....just missed getting this to you before you ordered another from LKQ. Curious what $$$ range LKQ has them at now? Last April/May they were in the $550-650 range + core return of the 10 bolt that came on most of our vehicles.....which they were selling for $12-1400.
The math didn't add up to me, so I (and this is what I was going to suggest to you) went the salvage yard route. It was not for the faint of heart though! By that I mean: you have a better chance of convincing a Grizzly to share a spawning salmon it snagged out of mid air while perched on the edge of a waterfall than you have of getting anyone at a junkyard to physically walk out to the axle and confirm it's a 14 bolt with spring perches! The only way to do it is to learn the VIN codes that indicate it's a 14 bolt 9.5" rear. Then use a couple of the free VIN search sites to find out everything you can about the donor vehicle. In my case that took about 10 days or so.... But once I had the VIN codes figured out (thanks
@swathdiver @Geotrash) I found a 14 bolt w/92,000 mi on it, out of a RWD '12 Yukon XL, 3hrs away for $212.00 and NO ($0.00) core charge! Saving that much money allowed me to put an Eaton Trutrac carrier in it and spring for high end bearings. I still have the stock G80 that came out of it if anyone reads this and needs/wants it?? Plus the 3.08 Ring/Pinion and the 10 bolt rear end complete with axles....
My theory was the 14 bolts are few and far between and likely RARELY EVER blow out, they basically only become available when the truck they were under was totaled. So they're simply not in demand, henceforth the low cost. The 10 bolts however have a VIO of 10million+, do blow up, and therefore are in demand, which is how these places justify the ridiculous pricetag for them.....smh! My plan was to rebuild the 10 bolt, coat it with POR15 and sell it for a few hundred less than the JEGS, Summit etc... Now if only I would follow through with that rebuild.....
As far as the four letter codes for the front diff?? I'm not 100% sure but I believe those are axle ID codes? Not gear ratio codes but axle identification. I was not able to find what they meant in about 15min of searching just now but did find this in the description of a Zumbrota front diff for sale:
front differential. With 3.42 Ratio. GM 8.25" ring gear, Independent Front Suspension (IFS), ratio option GU6, ID: AAAP, AAAZ, AABR, AACA, AACJ, AACU, BAAM, Hollander #440-01472, 440-01507. ***Call Zumbrota Bearing and Gear at 1-800-658-2537 ext. 125 for customer service, availability and technical assistance*
And I would have to think your logic is correct on which to choose based on it's similarity to your existing front diff axle code......HOWEVER this also is something I did not know existed, as I bought a GU6 front diff and called it a day......which turned out to be an AWD and you know the rest.....so at worst case, I would hope you would be able to Frankenstein any GU6 front diff with your existing front diff and make what you need. Which still leaves Frankenstein's twin, the front diff assembled from the parts you didn't need, in a fully functional and sellable condition...
-or-
One call to AAM or Zumbrota or Dorman etc.. would likely get you the answer to the AARB BAAB AABT question too. I'll be looking forward to the answer lol
