Dana 60/61 identification

[u2slow]

Wondering if there's an obvious casting 'tell' for the 61' or if all/most the castings Ford used had this extra webbing? My rear dodge 60 doesn't have it. Fwiw, this is claimed to be a '77 f250 diff in 4.10.

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The last time i saw this webbing, it was a 3.07 ratio Dana 61 from an 80's F250 diesel.

Anyone know for sure?

 

[Black dawg]

I have 4 354-410 ratio D60s here, from 77.5to 79 trucks, none have that webbing,

I think the high boy trucks did have that webbing

 

[Cant Write]

@david85 might know as he had a Dana 61 before converting to 4x4.

Just trying to help

 

[david85]

@david85 might know as he had a Dana 61 before converting to 4x4.

Just trying to help

Nope. I was running a factory Sterling 10.25" with aftermarket 3.08 gears (made by Motive Gear). Apparently it was a factory option according to my truck's owners manual, but I can't prove any that any existed in the real world. In any case, the sterling can accept 3.08 gears, even though the aftermarket stopped making them years ago.

My understanding is that the dana 61 was offered purely to allow taller gears for fuel economy in the mid 70s. I think most of them were semi-floaters but apparently many were also full floaters. Unfortunately, the book I have ("Differentials" by Jim Allen and Randy Lyman) doesn't mention any way to tell them apart from the outside. The pinion offset is different apparently:

Dana60: 1/2"
Dana61: 5/16"

EDIT: And apparently, the D61 was available with 3.00 through 4.10 gears, so that's no help either.

 

[Cant Write]

@david85 that’s what I get for trying to use my memory. Sorry for the assumption!!