early Ford trans ID?

[Louie]

I picked up a clean early Ford trans and the prefix on the left rear of the case is 48. Anyone know what year ive got here? Thanks,Louie

[Andy]

I think that would be 35/36.

[Homeresque]

I think thats 34/35/36. '32-33 V8 '18'-prefix. '34(model 40)-36 '48'-prefix. '37-39 '78'-prefix.

[286merc]

The serial # is down on the top front of the bell. Post that and I can get you the year as that is actually the vehicle VIN.

[Bruce Lancaster]

The 48 (1935 intro) casting was in comparison to earlier cases opened up in the first inch of the bellhousing area to be able to take bigger clutch sizes. Earlier cases have minor points of interference with 10 and 11" Long clutches. It was OEM in '35-6 only.
Next question with any early Ford box: What's actually inside after 65 years??
If the upper casting that houses the bottom of the shift lever is slanted back sorta like a shark fin it still has early innards and is likely an unmolested '35-6 trans with one of two slightly different gearsets.
If the upper casting has an entirely vertical housing for the bottom of the lever, it has very likely been updated with late Ford or Lincoln gears with the more modern synchro. Like any early Ford part, it's as likely to be a modified/mixed assembly as it is to be stock.