Another front diff ID Q

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boltbrain

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I just read hotrodPM’s helpful sticky on IDing front diffs. It says from 79 on, the 2500’s were GM corporate ten bolts. Mine is a 79 2500. But I’ve read that Dana’s are “ stamped” with a 44 or 60 facing the the T case. And mine has a 44.8 forged not stamped onto that rear, between webs. So am still wondering what I have. Any info much appreciated
 

dvdswan

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As you can see below... the Dana 44 is not as oval round as the GM 10 bolt.

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Bextreme04

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you could have EITHER a Dana 44 or a 10 bolt between 78-81ish. My 1980 has a 10 bolt, there is another thread on here where an original 81 heavy 3/4 ton has a Dana 44 front. The only way to know what you have is the case shape and the stamped code on the axle tube
 

nvrenuf

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@boltbrain Google for 10 bolt front axle pics, you'll see that the belly of the housing has sharp ears that hang down at the lower outer corners (maybe 1-1.5" square). The 10 bolt cover will also be fairly round (not perfect) all the way around whereas a D44 cover has straight sides with a rounded top and bottom.
 

boltbrain

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Thank you, definitely a Dana 44. Now I can shop for a knuckle. There was nothing but a pile of rust inside the hub when I bought it. The PO just left it engaged all the time as it never left the ranch. I got the cap, two snap rings and two round things out but the washer with the square gear like shape won’t budge. I tried heat, drilled and chiseled it in half, but it’s still not moving. Rusted to the washer behind it I guess.
 

bucket

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Thank you, definitely a Dana 44. Now I can shop for a knuckle. There was nothing but a pile of rust inside the hub when I bought it. The PO just left it engaged all the time as it never left the ranch. I got the cap, two snap rings and two round things out but the washer with the square gear like shape won’t budge. I tried heat, drilled and chiseled it in half, but it’s still not moving. Rusted to the washer behind it I guess.

Sounds like water intrusion and a lack of grease.

From '77-up, 10 bolt and D44 are the same from the knuckles outboard. Earlier year parts bolt on too, but there's differences in bearings, hubs, tie rod orientation, etc and you have to have matching parts for it all to work.
 

boltbrain

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Thanks, there is a D44 knuckle I can get nearby, how does the bottom ball joint come off? I don’t see how to get the nut off if it, it’s tight to the knuckle and between the U joint and the knuckle. The top one I can pound down on to get it loose.
 

boltbrain

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Just watched a good video on YouTube called Dana 44 ball joint replacement, and it shows how you have to start with removing the entire hub assembly and spindle, and since my hub and spindle aren’t coming out I’ll either take it to a shop or get a whole Dana44.
 

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