Eaton HO52. Usually has 4.56’s but depending on year can have 4.10’s (rare). They are a great solid rear but have basically no aftermarket parts available. You can get the common bearings/seals by number but thats it. Zero gear selection. I searched and searched for a while and found 3 and while hunting for 4.10’s for my truck and everyone I found was 4.56 until i located one on this site in canada and made a deal. Both my original 1949 rear and the newer c20 center section I bought were dead quiet and ran great. You will probably be good to go with a reseal and some fresh fluid if you dont see obvious carnage. If you need any more info (still limited) look up the HO52/HO72 on the 4WD forums. Some guys use them in off road crawlers.

1949 GMC 150
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