New 3240 owner with stuck transaxle issue
 

Hello everyone. I am a new user to this site. Unfortunately, I am joining because I need advice, but can clearly see the enthusiasm about Cub Cadet tractors on here and I find that encouraging. I think I'll be sticking around checking out your great posts. I can see you are a great online community that’s eager to see the Cub Cadet pedigree live on!

Now for my novel: First of all, I live in a small town, and have been push mowing my small lot for almost 15 years. I recently purchased a large property in the country, and will be mowing around 4 acres of yard. I decided to buy the largest mower I could find without breaking my bank, and settled on a used Cub Cadet 3240 with a 60” deck that was advertised locally. The original owner only has about an acre to mow, the unit was in fantastic condition, and thought the $1,300 price tag was a bargain compared to most other mowers in this size range. I test drove it around and tested the blade engagement and hydrostatic drive. The deck wouldn’t lift properly, but I could see the obvious problem. Also, the seat didn’t want to adjust, and it was stuck forward. *NOTE* It has about 650 hrs on it.

I removed the deck, and put the mower on my trailer separate. I drove it home and parked the trailer in my garage to repair it where it sat. I had to replace the right side deck rod as it was snapped off, but that only cost me about $20 to fix. The deck lift should be good now. I was able to blow out the dust and grass clippings and lubricated the seat rails. All is good now. While I had the seat off, I used compressed air to blow off the buildup of usual junk from the transaxle area. I put the seat back on, started the mower on the trailer and double checked the deck lifts. All seemed great, and I couldn’t wait to use this bad boy! I set the parking brake and tied it all back down.

I drove it to my new property yesterday and removed the tie down straps and started it up. I disengaged the parking brake and began to move the mower backwards off the trailer. After moving about 2 ft or so, the mower stopped. Weird I thought, but jumped off to see if I left on a tie down or if my loose deck brackets had caught. Nope! Everything looked good! I started it back up, and tried again. Same thing. No more reverse. I pulled up to the front of the trailer and tried it again. Same thing, and it stopped in the same exact spot! I tried this several more times, and it would always move up to the trailer front, and back down normally until I got to the same spot. When the point that it would stop moving was reached, I could hear it load the engine and the transaxle would groan like it was really trying. I thought that I would try pulling out the lever that is supposed to free up the trans so I could at least back it off. Nope! That wouldn’t work either. I turned off the engine, made sure the lever was locked into the outmost position, and tried pulling it off. I rocked it back and forth, and it wouldn’t budge.

At this point, I was starting to see red! I started the engine back up and pulled it back forward. After a few more attempts, it actually moved about a foot more backwards from where it would stop in reverse. My wife clapped and hollered “progress!” Personally, I wasn’t feeling the moment. I thought ok, maybe if I get this thing off, then I can get it level and try it off the trailer. Unfortunately, I now noticed it had limited movement in the forward direction too! It was now stopping about a foot shorter than where it would before! It would move in reverse to the new spot further back and stop, but now I couldn’t get it all the way forward either. I turned off the motor and tried a couple of more times to unlock the rear axle, but it wouldn’t move an inch. I did check the axle fluid, but the trailer isn’t allowing the tractor to be completely level. Besides that, its level indicates between the tip of the stick and the add line. I’m picking up some Shell Rotella 15W40 after work today and adding some, but I don’t think it will make that much difference. My real concern is that the axle is shot since I feel the tractor was stopping at predictable positions. It’s as though an axle component allows limited rotation and physically stops the tractor, and allows only limited travel.

FYI, I tried holding down the axle lock pedal, and there wasn’t any perceivable difference in behavior. Also, I was careful to strap this tractor down using only the frame and not any linkage. I don’t know if I backed it in reverse the same length of my trailer or not when I test drove it, but I didn’t notice anything.

So, now I’m leaning on you guys to give me some advice. I think this mower is a supreme product as it's made right here in Amercia, but the carpet has been yanked out from under me emotionally. I have a really nice $1,300 paper weight that is stuck on my trailer, and my new yard is quickly turning into a jungle! I’m really hoping that I wasn’t just taken to the bank here! I thought my judgment was better than this, but I’m glad I didn’t check out this mower for a friend or relative only for them to have this experience.
I would GREATLY appreciate any advice you can give me. Thanks in advance!
Greg

Greg

Think you want to talk to Oak, he knows a fair amount about this series.

Here are a couple threads about 3240's seems as though they have some issues with the diff lock.
http://www.onlycubcadets.net/forum/s...ad.php?t=38321
http://www.onlycubcadets.net/forum/s...ad.php?t=26375

Thanks Sam Mac. I read through these two threads, and have an idea. I have not yet tried to jack up the rear tires and see how they move. That might give me a chance to listen for any mechanical noises too since the engine will be off. My problem is that it's on one of those "caged" mesh trailers without a true solid bottom. I'll have to connect the trailer to my Cherokee, chock the front tires, and slide a supported jack under the rear to try this tonight after work.

One of the posts had a link to this rear end "I think Oak actually provided this" in an exploded view. I'm wondering if I can also check these bolts that a couple of people referred to.

Does anyone know if I can get a peak inside this case without a complete tear down? It would be nice to inspect the bolts Oak refers to as part #17 in this diagram link:

https://polr.partstree.com/v1/iplima...I7aToxMDAwO319

Update:

Tonight I added about half a quart of oil to the transaxle. This brought it to the top of the full mark. I started the tractor and backed it off the trailer until it bound up, and then I moved it forward until it stopped. I tried it 3 times to no avail. Same symptoms.

Next, I rigged a jack under the back and lifted it until the rear tires came off the trailer. With the axle in normal position (not unlocked) I could turn the rear wheels as much as I wanted to. When I turned one wheel, the opposite wheel turned in the opposite direction. There was a mediocre amount of resistance to turn them. As I turned them, I could feel a deep pulsing from the mechanical side. Perhaps the pump??

Next, I pulled out the rod at the back which unlocks the axle to be pushed. Doing this didn't change anything. I could still turn the rear wheels, but with no less resistance with the diff axle locked. Next I put the rod to locked the axle again and tried. Same ability to turn the rear wheels and with the same amount of effort. I had my wife push down on the diff locker pedal on the left side while I turned the rear wheels. As I began turning them, I heard a small clunk from the transaxle and the rear wheels locked. Once they locked and while my wife held down the pedal, I could not budge either wheel. I pulled out the back rod to unlock the diff so it could be pushed. The wife held down the pedal and I got the same locked condition without any ability to move either wheel. She let go of the pedal, and I was able to move the wheels again the same as before.

I will note that during this entire ordeal, I never once heard any strange mechanical noises that would indicate a loose bolt or anything grinding, etc. inside the diff case.

I'm really beginning to wonder what could be holding the inside movement that is preventing normal operation but is allowing free wheeling with the wheels off the ground.

I double checked the diff lock cable from the pedal too. It is loose enough to disengage the rear end when not pushed down. The brake pedal manipulates the rear diff lock pedal anytime you push it in, so I wanted to make sure this wasn't partially engaged with the brake pedal when the brake is relaxed. This looked fine, and I even tried to gently push the diff lock cable back towards the rear of the diff.

Any other ideas? I'm heading to bed now. I get up at 3:45 am!

Greg

My guess is that Oak will chime in tomorrow AM. Hang in there.

Greg, welcome to OCC. I'm sorry to hear about the issues your having with your new machine so lets do a little checking on the easy stuff.
How does the power steering and deck lift work? If they work normal and you can turn the steering wheel several times lock to lock with the engine running then that may rule out your gerotor. I have not had a gerotor fail yet but I have read about some of them failing. I would also take a close look at that rear for any oil leaks. Good luck and let us know on these things before we move on to the next step.

Thank you Oak for chiming in. Looking at your many past contributions, you seems like a master at these machines. A master is what I may need in this case!

Yes, the steering moves back and forth to the limits just fine. I tried angling it back and forth some as I was able to get my limited travel up and down the trailer. As far as the deck lift goes, I can't test that completely, but I believe it works ok. When I purchased the mower, I removed the deck because it was too wide for my trailer. One of the lift rods that connects to the deck brackets was broken and I replaced that. Both brackets seems to go up and down as I would expect them too.

When I had the rear lifted last night, I turned the rear wheels quite a bit. I was hoping for a clue like an obvious noise and I also expected for at least the same kind of mechanical limits on the amount of travel. I figured I would only get about one full rotation and then stop, but I didn't get that. As one wheel turns clockwise, the opposite turned counter clockwise. I could not get both to turn the same direction. I sort of understand the concept of how a diff works, but if both wheels turn at the same time when driving, why can't I turn them both the same when lifted??

My wife held down the diff lock pedal, and that would prevent me from turning either of the wheels.

Is there anything outside of the transaxle that could limit this travel? I'm assuming the shaft running from the engine to the transaxle turns constantly while the motor runs, correct? I'm just trying to think of anything mechanical that could bind this besides the transaxle. Is the gerotor the same thing as the hydraulic pump? I wasn't for sure where the pump is, but was assuming the shaft with the plastic cooling fan on it was connected to the engine and hydraulic pump. Sorry, still learning the ins and outs of a hydrostatic transmission on a mower. I work on the new Chrysler 8 speed transmission at the factory in Kokomo Indiana, so I would think I could figure this bugger out too! I'm going to review the link to the service bulletins today at work if I can sneak it in so I can get a better handle on the mechanical brains. Must wait for the coffee to kick in first!

When I removed the seat for repairs, I took the time to blow off the debris from the mechanics underneath. There was quite a bit of dirt and grass build up. Some of the dirt was a teeny bit wet from what I suspect is hydraulic fluid. I have this parked in my garage and so far not even a drop of oil has dripped through the trailer floor onto my fairly clean cement garage floor. The trailer floor is that caged wire type so any leaks will fall thru it. Otherwise, I added half a quart of fluid to top it off, which indicates it must have a small leak somewhere!

Another quick question to throw out there. I was perusing through the cast iron transmission service manual and had another idea. Is it possible to turn one wheel and allow the opposite wheel to turn in the opposite direction without turning the brake disk on the side of the transmission? If it is, I might have something binding in the brake assembly. After all, I drove this for about 50 miles on a trailer with the parking brake engaged, left it sit on my trailer in my garage for another week (with the parking brake on) and then drove it another 40 miles on the trailer with the parking brake on. I can see in the manual that the brake disk has holes in it (for cooling??) and could possibly be catching somehow as I move forward and backward and could be hanging up somewhere as this brake disk turns.

I can check that this evening.

Just trying to brain storm here....

First I'm not familiar with your trans axle as in having one apart.
I looked @ parts tree diagram and understand the system.
A ray of hope here:
I am thinking you just might get lucky in as much as your description of the long trailer trips it underwent, rocking back/forth.
It is possible that the notorious loose bolts that hold the diff/ lock assy together, decided to back out during the trips and are what is locking it up.
Hopefully as it was not being operated when it happened as your test drive was successful, the damage will be minimal.
Now back to the others who have BTDT. :beerchug:

If one of the bolts have backed out far enough to bind the diff lock assembly against the case, will this allow the wheels to still turn? I believe it should still allow me to turn the wheels within the assembly since the spider gears (or whatever they are called) should allow me to, correct? If I'm correct, you are probably right. That might explain why if I hold the diff lock pedal down while turning the wheels with the back jacked up, I can't move either wheel with my own strength.

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.

A couple of scoop shovels under the wheels sliding down the ramp ?
Remove 1 rear wheel, allowing the remaining one to roll ( spider action) and the axle flange will slide down a plank on the removed wheel side.:bigthink:
just remember you have no brakes.

Greg, I'm not 100% sure because I haven't pulled one apart yet but looking at the parts breakdown it looks like if you remove the hub the left side cover should be able to be removed. I'm thinking that the pump shouldn't have to be removed. Please take some pictures for us. Good luck!

I do have the service manual for this, so I think I'm in good shape in that respect. I believe that if I remove the wheels, the wheel 4 pronged hubs on each side, then the left side of the case should come off. Once that comes off, I'll need to remove the diff lock arm. Last, I think the diff assembly with both axle shafts should come out. That seems pretty straight forward. I just wanted to know about the pump as it might be easier to remove it now on the mower before I start chasing this thing across my garage floor!

As for getting this off my trailer without crushing one of my feet, I think I'll use a piece of plywood clamped to the trailer ramp, and lift the mower rear with the saddle floor jack and begin backing it off slowly with a come along attached to the front. Don't worry, I'll remember to hook the trailer to my truck first! I figured once I get the rear tires on the garage floor, I can basically pull the trailer out from under it. If I had some of those dollies that would help!

As far as pictures go, I'll definitely take some to post.

I'm still going back and forth with the probe camera idea. It's $80 and I would really hate to take this whole thing apart in vain! I can almost hear the chanting though from the members.

"Take it apart! Take it apart! Take it apart!" like little inquisitive minions dying to peek inside somewhere they've never seen. To bold go where nobody else has.... kinda like tractor trekies!

Looking at the manual I have my bet is one of the 9/16" bolts that hold the diff together backed out and it is catching on the inside.

Think we are all there with ya Sam, especially with that model's reputation of doing that.
Now on with with the show, the suspense is unbearable Ha,LOL!
:popcorn:

Sam, I'm also betting you're correct.

I went by the local Chinese tool outlet to look at their camera scope. Once I seen the diameter of the camera and the inflexibility of the camera shaft, I determined that their model wouldn't really work for this particular job. Justification for a new toy was lost.

So, I went home, ate my supper, and only got to spend about 1 1/2 hrs to work on it. First order was to clear a space to move the trailer partially out of the garage. The wife took my son to 4H shooting sports to fling some lead and took the dang Cherokee. So after tearing apart the garage looking for my hitch ball for the Impala, I finally remembered that I had it tucked away in the trunk. Must be Alzheimer's.

Anyway, I was able to pull the tractor off the trailer using my floor jack and moving one wheel chock against the front tires, moving it about 8 inches at a time so I wouldn't lose control and smash my foot. It was slow, but successful.

I intend on doing this process with as little effort as possible. I've detached the linkage and two hydraulic lines going to the charge pump. The drive shaft going to the engine is also loosened. I noticed that there is almost no clearance between the shaft and the attachment point where the plastic fan is. That tells me that I need to leave all bolts loose holding the rear transaxle assembly until this shaft is tightened when I reassemble everything. Otherwise I might add stress to the front hydraulic pump bearings. I also marked the positions of the bolt washers on the four bolts holding the axle to the frame in order to maintain this orientation when I put this back on. I don't want to screw with the alignment.

That's about where I stopped last night. I was going to try to remove one of the hubs, but I need to buy a 1 5/6" socket. Biggest I have is a 1 1/4". Just another excuse to buy more tools!

I was reviewing the cast transmission service manual, and I'm thinking I might need to remove the hydraulic pump now. Looking at the pictures, It appears that the 54T bevel gear will need to be removed at the same time the diff assembly comes out. This is because of the engagement orientation of the 60T spur gear to the output shaft. I guess I'll see if I can wiggle it passed the output shaft. If not, then I will have to remove the hydraulic pump because of the input pinion which drives the 54T bevel gear. The service manual simply states to use a soft mallet to remove the input pinion and bearing. I have this sinking feeling that this may not just fall out either.

Also, I'm just trying to think ahead some, but any ideas as to what might be best to seal the two cast iron axle halves together? I have some cork material that I can cut a gasket from, but that might add too much clearance to the internal shaft thrust bearings and washer surfaces. Any suggestions here? The service manual mentions Loctite sealer is used at the factory. Considering that this mower is 14 years old, this product may not be available. Also considering the necessity for a sealant to cure, I may not be mowing this weekend anyway. I'm praying I can squeeze past the output shaft!
:Pray:

I sure wish that Cub Cadet had put some kind of removable plate on these things!
:bash2:

I use Yamabond or Hondabond on any mating gear cases.
And have for about as many years as they have been importing them mo'skkles into this country.
For good machined surfaces, it works very well.
I don't like silly cone in this application, it dissolves too easily.
There are other crank case type adhesives that work just as well.
I'm sure Harley Polaris etc etc all have equivalent.
I have never had a leak using them.
easily available @ any shop/dealer.
Newer thinking has gone away from costly gaskets and is assembly line friendly.:beerchug:

@t6430gr:
Afraid I too have the same problem as yours.... only my loose bolt came out the bottom of the cast iron transmission via the hole that it created as it got caught up in the gears. I have, in vain, been looking for a used replacement transmission locally. Best I could do is brand new at $1400 and just can't bring myself to spend that kind of money on my old 3240. Having decided that, my plan is to rip into the transmission, probably start this weekend. I have never done any transmission work but I am pretty handy. You mentioned you have the service manual for the transmission. Do you mind sharing where you got that, seems a bit handy for my future endeavors :)

Anyway keep us posted on your progress and I might highjack this thread along the way to seek advice as well (if that is ok).

Thanks.

Here is the link to the manual. Lots of good stuff here.:beerchug:
http://www.mymowerparts.com/pdf/Cub-...epair-Manuals/

Now you guys got me thinking I need to pull mine and check it.:bash2::biggrin2:.....maybe I'll see how difficult it looks first. Lots o pictures please.

Thanks for posting the link Oak. This is the same site I got the cast iron trans service manual. I think it is pretty well done.

I was only able to work on it for a short time last night, which drives me nuts! I stopped after work and picked up a 1 5/16" socket so I could remove the axle nuts that hold the four lug hubs to the axle shafts. After the nut was removed from each side, I was surprised that I didn't need to fight with the hubs. They came off nicely! I did put these nuts back on in order to protect the threads while I wrestle this around on my cement floor. So by now I had the body of the tractor supported, and there was nothing left to do before dropping it from the frame. As I supported it with the jack and began slowly lowering it, it became hung up on something. It seems I overlooked the axle lock cable! :bash2:

I raised it back up and got that removed, and down came the transaxle. After plugging the two charge pump holes with cotton balls, I used compressed air to blow off the dirt and debris around the case bolts and mating surfaces. Next, I removed all of the case bolts from the perimeter of the case. This is where an air ratchet paid off. So many bolts!

Next, I tried to begin splitting the two halves. I think ol`George will need more popcorn because this may take awhile. It seems that Cub Cadet designed the case in such a way that there are no protrusions from the perimeter of the case to pry on or tap with a flat steel tool. NADA! I tried whacking on it some with a rubber mallet. :beatdeadhorse: It won't budge! There is just simply too much surface area being held together with the sealant. That's where my evening ended. I was eager to at least get a peak inside last night, so I was very disappointed.

Now I'm devising a plan to get this apart. I'm thinking about fabricating something that will allow me to be fixed against the two axle shaft holes and push against the axle shaft itself. This will provide a push/pull scenario that I'm hoping will break the bond with the seal. That is some good stuff! I have a feeling that getting this apart will take a majority of my evening today which really bums me out. It tends to tick me off when I work on things like this when companies engineer something without the ability to easily service it. I'm betting that the guys servicing these units are/were great at cussing.

God forgive me for the language that bounces around my head when working on this kind of thing. I do believe that a son-of-a-:censored: might have fallen out of my mouth yesterday! I made sure to sweep it up with the oil dry and misc. dirt on the floor.

I'll be sure to post pics once the case is cracked open.

Sounds like a plan :beerchug:
:popcorn::popcorn:

A light "tap-tap-tap" with a small steel head hammer, around the "seam", will usually break the bond, from the slight vibration, shock. It may take more than you expect, so be patient, and not get too ambitious with the hammer! Others, may have a better solution. :BangPC:

I'm trying to not use the hammer as I usually see it as a tool of last resort. Of course, I do have a nice variety of smashers! Since the material is cast (brittle) I'm avoiding the destruction of this as much as possible. I prefer to pull this straight off as there are two shafts that are supported on each side. I don't want to twist this into submission because I could cock a bearing. I want to be aggressive without destruction.

That can be a delicate balance when one is overcome with impatience!

Thank you very much for the link Oak!

Well gents, here's the scoop om my issue. I was able to finally get this apart, but I wish I hadn't as our suspicions were correct. To get the case apart, I reinstalled the four bolt hub, and also the two axle bolts that attach to the frame. I used two large C-clamps to push/pull the axle against the case. It popped right open with me beating the case to death! One hint here, before opening your case, use a flat file or fine grit sandpaper to remove the rust on the axle shaft as the clearance on the bearings is tight. If you don't you'll encounter resistance pulling off the outer case plate and again when you pull out the axle shaft assembly.

Needless to say, depression set in a little bit once I got it apart. From the pictures, you'll notice the bolt hole and exposed threads. If you can peak inside your case with a flashlight through the dipstick hole or a small camera, and you see exposed threads, you are experiencing the same thing. This is where you stop and make sure you have a 12 pack of beer to get through the next couple of days. Note from this view, you can see the clearance between the drain plug and the diff gear. Before you try to pull out your diff assembly, make sure this plug is backed out first. Also, some good news I guess. When you take your diff assemble out, you don't need to remove the hydraulic pump. After the case is open, the next step is to remove the diff lock. at that point, you can start to pull out the diff assemble and axle shafts. The output shaft that connects to the ring gear and rides on top of the diff gear will start to come out too. Just wiggle the output shaft an inch, and pull out the diff assembly an inch. Eventually, the brake disk will come off as the output shaft extends through the case and turns the brake disk. Note the orientation of the disk before taking it off. As you continue this back and forth motion with the output shaft and diff assembly, the output shaft will disengage from the ring gear and the ring gear will ride on a smaller diameter of the output shaft. These two connect on splines. Once the ring gr=ear is loosened, you'll notice there is more freedom to pull out the diff assemble without the output shaft's need to ride out any more, and should be able to clear the large diff gear. Just be careful to not force anything here. If you feel resistance, you probably need to push the diff assembly back in a little and pull out the output shaft a bit. If you pull the output shaft totally, it's no big deal. There is a flat thrust washer behind the ring gear that you'll lose along with the ring gear itself.

The gears inside my diff assembly have a pretty worn wipe pattern and will need to be replaced eventually. The ring gear is also damaged. I tried to file off the burrs on the outside edges of the damaged teeth, but the gear was harder than my files. I had to surgically grind them off with a Dremel tool and cut off wheel. That made short work of that task! At this point, I think that I can get away with putting this back together and nursing it along for a couple of years. Eventually I think I will buy a new set of gears for this and rebuild it like it needs to be. My goal is just get it going for now, and a rebuild will be better suited in the off season.

Another couple of comments before I go. I found replacement grade 8 bolts (3/8" x 24 tpi) at my local hardware store. Before installing them, I sprayed out the thread holes with brake cleaner and put a drop of Loctite thread locker on each one. The bolts I purchased were just slightly longer than the originals. If I had about another 1/4 inch, I would have plenty of meat to attach a nut on the extra length for good measure. I don't know if that would be necessary or recommended, but considering the fact the bolts tend to loosen, I might do that when I rebuild it next time. There was enough clearance between the diff lock and the nut I tried to make that feasible. These bolts are supposed to be torqued at 220 - 280 inch lbs. My 3/8 drive torque wrench stopped at 250 inch lbs so that's what I torqued them to.

So, last night I got everything put back together except for one last item. It seems I have misplaced one flat bearing washer that goes between the diff lock and the next bearing on the outer case cover. Don't know what happened to it, but between myself and the wife tripping over tools and other items on the garage floor, it's hard telling what happened to it. I guess I'll have to check at the local automotive store for a replacement or order another online. I can't put this back together until I find it, so I went to bed last night ticked that I lost it. It's part number 24 on the parts diagram.

I am surprised @ the wear on the 4 spider gears, chipping I understand, but one heck of lot of wear on the contact surfaces, for the stated hours.
It appears they are through the case hardening in places.
So you are going to take it easy and avoid any "hole shots" then as time permits replace the worn items in the off season,----reasonable plan.
Wondering if nutting or safety wiring the bolt heads, is advisable.
The bull gear does put all the driving motion through those 4 bolts, I sure would like to see @ least 6 or even 8 bolts taking the strain.:bigthink:

First time I've seen the inside of one of these. I wonder if you could put longer bolts in it and after torqueing it put some lock nuts on the back side? Don't know if there is clearance or not, just a thought.

I agree. I had the chance to get 1/2 longer, and I probably should have to put nuts on the back. The size I purchased were about 1/16 longer than the originals. I think that locking washers might work if they could clear the diff lock unit when it engages. I did check and a nut would clear the diff when it engaged. I hadn't thought about wiring them, but I would probably need a machine shop to modify some bolts for me, as these are grade 8 and pretty darn herd.

I will baby this along and maybe work on it this upcoming winter when I won't be mowing multiple acres. I'm thinking more in line on something Oak does to his, meaning really dig into it and replace all gears and seals too. I can see plenty of oily dirt on the deck lift spool and cylinder. I'm sure they need rebuilt too.

I agree whole heartedly. All of that wear translates into a ton of loosey goosey in the axle play when I rotate the tires back and forth in either direction. I'm really hoping that the hydraulic filters do a good job or I'll be rebuilding it too. I guess all this work is a lot cheaper than the comparable cost of something new. I don't usually buy anything new in this kind of price range. I tend to buy cheap, fix it, and take care of it. I paid a guy $1,300.00 for this mower because I was impressed how clean it was. I have never purchased a mower this big or complicated and I think the seller knew something was wrong. He was just damn lucky that this mower drove nice when I was on it! It was a nice mower in a nice neighborhood with a well groomed lawn and he was a very nice guy. I doubt he was clueless to any issues as the extent of wear indicates that this has been going on for awhile.

I can tell you though, the transaxle is on my garage floor right now, reassembled, and the fresh sealant is drying. I tried to turn the axles after I buttoned it up, and it feels so much more free!

It will probably be trouble free for the rest of it's life. This is part of the deal buying used, you have to figure you will need to put some time and $$$ into it. In the long run it seems to work out. :beerchug: