Question on rear diff.

47 K-1. I have heard about a two speed diff, and was wondering if that is what I have. There is a small plate, shaped like a T that goes into passenger side of diff and goes between two gears. But it have no cabling to it, its just a cover plate more or less.
Is mine a two speed diff, that just has the cover plate and no mechanism to change it? Seems odd that you would have to crawl under truck to engage that gear. Did they make a two speed diff and have an option, for a cable to make it function? Thanks.

2 spd rears were only used on the heavyer trucks, K-5 and up. Much bigger rear (with dual wheels) than you have. A picture of what you are trying to decribe would help.
2spd's are shifted many ways, mechanical link, vacuum, air and electric have all been used. They are designed to be shifted on "the fly".

I have several of that era diffs and can't think of what a "T shaped" plate is.
We need pictures!
Old diffs sometimes had a ring gear rubbing block..
These are "drop-out" differentials..NOT "integral" housings...
I suspect it's a snap ring cover?
Now I can't stop thinking about it...
Put us out of our misery.
No two-speed diffs on this light stuff that anybody here has seen.

Sorry for getting back late, was spraying epoxy on diff. and springs. Here's some pics and a crude drawing of what it looks like taken off. (paints too wet to remove).

I think it's a snap-ring cover plate.
I will get stampeded to the truth..

The truth will set you free.... Or not.

If I am seeing what I think I am, that is the snout of the pinion, my guess is what you think are "gears" are bearings, or bearing adjusting nuts and that snap ring or adjusting nut is a way to adjust the bearings. I have not worked on light K rears, but have been in most types.
I'm guessing you rotate the "gears" to set the bearings and a snap ring of some sort holds the adjustment. I'd have to see inside to be sure.

Let me, let it dry a bit and I'll open it up for a pic.

only light duty vehickle that I know of two speed axle, would be Ferd Lincoln with Columbia 2 speed rear axle,

that is not what you are showing, like CB posted 2 speed axles (back then) are big units,

only light duty vehickle that I know of two speed axle, would be Ferd Lincoln with Columbia 2 speed rear axle,

that is not what you are showing, like CB posted 2 speed axles (back then) are big units,

Today, also. I have a set of Eaton DT402's in my Marmon. While 2 spds have lost some sales to the newer 18 spd gearboxes in semi's They really shine with heavy loads, the 18 spd put all that torque thru the driveline, the 2 spds allow less torque and less reduction up front, and the only parts that "see" the full torque are the 1/2 shafts.