Hi folks. New to the forum. Just bought a 2005 Express 3500 cargo van. 34k miles. 4.8 engine (laughter may be appropriate) 4L80E, cruise control 4 wheel discs. VIN and RPO codes check out, says rear axle ratio is 3:73. My question is the axle is an 8 lug semi-floater with a 12 bolt cover! I can't find any references for this axle. There is a bar coded sticker on the driver side axle tube with the number 65XH3 M43450076. This number is also etched into the right side axle tube. There are no other tags. There is a diamond shape casting mark on the right side upper diff. Housing that looks like AAM. any ideas?

 

Late last night after my initial posting I found info on the Pirate 4X4 sight. Apparently the axle in question is model of Spicer 60. I forgot to mention that there is number 248 cast into the lower web of the diff. housing. It seems 248 is the metric measurement of the ring gear size and this axle is being used under Express/Savanna GM VANS. I went to the spicer website and it lists the axles as 60/248 spicers. These axles also have a 12 bolt cover plate. Not much info even from the axle specialty shops.