Gearbox - coded 4b20a

[Matt Elan]

My brother in law has just dragged an old Ford gearbox out of the depths of his shed. Its a Ford four speed type but is not a 'normal' 2000E - presumably my BIL collected it in the 70s when it was removed from a rotted out saloon of some description. It has the code 4b20a stamped on the tag bolted onto the top casing. I've had a rummage about on the internet, Burtons catalogue and a couple of other places but I cant find a reference to the coe - apart from it being a hydraulic lifted for a Ford tractor....
Can anyone id the box for me or tell me where to look for more ID number(s)?
Thanks
Matt

[gjz30075]

That's a date code. 4=1964, b=Feburary, 20=day of the month, a= most likey 1st shift

Here's a good reference for Ford date codes. Varies a bit from cast parts, to sheetmetal parts and
varying mfgrs
http://automotivemileposts.com/ford/for ... mbers.html