I'm looking to swap out the 4.56 10 bolt in my 42 3/4 ton. The tech article on this site recommends using the diff, carrier and front case from a 55-62 1/2 ton. Sounds practical except for one thing. Thus far I have been unable to locate a 55-62 1/2 ton rear end.
Anyone have any tips as to who may have one of these available? Naturally, I'd prefer a 3.38 ratio but the 3.90 would still be a big improvement over my 4.56.
Any recommendations for using a different rear that will give me better highway speed in my 42 3/4 ton would also be appreciated. I prefer something that will bolt in without major mods. If I have to mod the driveshaft, so be it.
BTW, my truck is running a 62 235 with dual Rochesters and Fenton headers. The trans is the original 4 speed with granny. I'd like to keep the trans stock.
Thanks in advance.

Tom
1942 Chevy BL 3/4 ton
1942 Dodge WC 1/2 ton
1960 Mercedes-Benz 190SL


Ghost Rider
Little Egg Harbor, NJ
1942 Chevy 3/4 ton pickup, 1962 235, Offy intake, Fenton headers, Dual Carter YFs, 1984 T5
1956 Chevy 3100 Apache, 67 350SBC, Saginaw 4 speed, 69 12 bolt