I have no experience with this trans, that said from reading the other posts and about your situation, I think this is a plausible scenario. It sounds like the ones that blew holes in case happened at speed, since you were (presumably) slowly backing off the trailer it didn't have the force behind it to break throough the case so it just bound up. If it were mine, I would pull the rear cover and see what I can see.

Bill

You are correct.
#10 collar slides on axle spline #11, into #13 locking it together and negating the differential spider action.
You have a good understanding of the differential operation.:beerchug:

Bill, these rears are different and have to be split in half and don't have a rear cover like the aluminum 3k rears or older machines.

Okay, I just jacked up my good running 3240 and I can not turn both wheels in the same direction but they spin nice and easy if I spin in opposite directions.

I have a GT3100 on the OR table now with the fluid drained out of the non locking differential cast iron rear and if I spin the wheels in opposite direction the brake disc does not turn. I can spin the wheels in the same direction on this one I guess because the fluid is out of it and the brake disc does turn.

Maybe you can drain your fluid, jack it up and see if you can spin it by hand. I would also look close at the fluid to see if there is any signs of metal in it.

When I get home this evening, I will remove the seat and inspect the brake assembly closely. After all, I did blow it off with compressed air. I think the brake won't spin while turning the free wheels if the hydraulic pump is in it since it mates to the large ring gear. Not sure though without my own OR table. :biggrin2:

I also don't see clearly where the unlock/neutral rod connects in these service manuals or how it allows the trans to free wheel. This functionality isn't working on my tractor and is probably a clue. I just can't visually see where it connects. I might be overlooking it.

I'm toying with the idea of also getting one of those cheap USB camera's if I can get one small enough to fit inside the top hole for the vent cap. If I wiggled it just right inside, I might be able to see along the large gear on the diff assembly and see if any bolts are backed out. Plus, I would be able to give myself my own colonoscopy in the future! Oak is correct. I can't just pop off a cover on this cast iron model.

If I do drain the oil out, I'll be sure to capture it in a clean container and inspect for depression flakes.

Looking at the pictures in the service manuals, it appears to me that longer bolts could be substituted on the diff assembly and perhaps some nylon locking nuts installed with split washers on the extended threads after they are torqued down on a pool of Locktite and then spot welded. Just a thought...

I think properly torqued and locktight the #17 through bolts will be the way to go.( replace them of course)
I don't like welding on heat treated bolts, and it's overkill I'd say.
Make sure the threads are clean/dry when applying locktight so it can do it's job.
The camera idea intrigues me, I thought about is also previous, and like any tool, you find many uses for it.
Now about that colonoscopy, well not this time, The gubber-mint seems to be doing a good job of it already Ha,LOL! :bigthink:

I'm thinking with the oil out you can spin it.

The release rod connects to a thin metal plate (#4) in the Transmission mounting and neutral linkage diagram. This plate pushes in on the bypass valve (#29) in the Hydrostatic Transmission diagram. Maybe yours is broken.

Sorry, that was mostly sarcasm. I stopped short of saying to bend over any excessive threads like the highway dept. does on street sign bolts! Of course I don't even know for sure if that is my issue yet, but we'll see. I think I'll swing by my local Chinese tool outlet store and see what I can buy. A couple of years ago they offered a small scope camera for about $50. It might be worth it.

Sorry, my mistake. I will go back to lurking on this thread and hoping for a simple (cheap) fix.
Good luck!

Bill

Took off the seat, rear frame cover, and rear plate. I inspected the brake assembly and unfortunately it looked fine. I was really hoping to see a bolt dangling from one of the holes in the brake disk.

I also went ahead and drained the oil from the transmission axle to inspect for debris. I felt it was fairly clean with only a small amount of shiny floaty's at the end of the drain process. No hard pieces or chunks thank goodness!

I was going to run to my local Harbor Freight Tools and buy a camera scope, but the online reviews were not very good. I believe that having one could come in handy, but I think I'll save my greenbacks until I can investigate other options.

So, at this point I'm really leaning towards taking off the transaxle and start taking it apart.

Oak, question for you here. Since you have one of these on your OR table right now, can you tell me if I need to remove the hydraulic pump assembly to get out the axle shafts and inspect the diff assembly? I want to make this a minimal effort as time is of the essence to me. I am in the middle of having two properties now and trying to move, work, get my current home ready for market, make it to all my son's games, and hopefully get some sleep in there somewhere! I would love to do as you and take the time to fix every detail (I think my deck lift spool is leaking) but I want to get this mower going last week. Any suggestions on how to make this a minimal effort?

Tonight I will devise a plan to get this tractor off my trailer and begin to get things cleaned up some and remove the hydraulic lines and get the tires loose.

I have a copy of the 3000 series service manual, pretty sure Oak sent it to me. Unfortunately I can't e-mail it because of it's size and my crappy internet provider limits the size.

As far as getting off the trailer if you have a couple of those furniture dollies you could put 1 under each wheel.