I'm sure this is a dumb question, but since I don't know the answer, I thought someone in here might. I'm considering trying to use a 94 .38-55 barrel on a 92 and wonder if there are major problems inherit in this switch?

If you are going to leave it the original caliber, 38-55, it won't work since the 92 was chambered for "pistol" cartridges such as 44-40, 38-40, 25-20, 32-20 and in different model numbers, 218 Bee and a few others. The overall length of the action prevents if from using any cartridger longer than those mentioned.
As for the thread size, I have not seen one apart in many years, but I think the threads and barrel shank are smaller on the 92. So you could turn the 94 barrel down to fit...I THINK.
The question would be is what caliber would you chamber it for.

Congomike:

Thanks, I knew it was a dumb question. Nothing new for me. I was sitting here "thinking" (and I use the term loosely) over my first cup of coffee and thought, "I've got these 92s that have crapped out barrels in them, I've found these .38-55 barrels, why not? Again, thanks and sorry for the dumb question.

Gatogordo -

I've never tried this, so am just sitting here over the first coffee of today, day-dreaming along with you...

You know, if you do your own machine work (so you don't get too much money into all this) it may just be possible to make those .38-55 barrels into "real" .38-40 barrels....that is, barrels using the basic .38-40 brass and real .379-.380 bullets.

I suspect one could cut off the breech end of the barrel, re-chamber with a neck and throatless .38-40 reamer, then cut the neck and throat to fit the .379/,380 bullets.

They chould feed with no problem, as they would be the same length as the original cartridges, and very similar in all of the case body dimensions.

A lot of un-needed expensive hassle if you were paying to have it done, but kind of a neat project if doing it yourself.