T503 4 Wheel Drive Problem

[Chaos USMC]

Howdy Folks,

I own a 2010 TYM T503 with a little over 500 hours on it now. I am ahead of the curve regarding maintenance and respect it during operation. It has been a very dependable machine but having said that, I was clearing snow yesterday and lost my 4 wheel drive ability. A major problem since my snow covered 300 yard long driveway is up-slope.

When the problem occurred, I began to hear a cyclic clicking, nothing major by any means. I almost ignored it... I asked my wife at one point to listen to see if she could tell where it was coming from and she said it sounded like it was somewhere under the tractor seat area. At that point the clicking was roughly 2 times per revolution of the tractors rear tires. At this point I still had 4 wheel drive. When I was preparing to put the tractor in the barn I decided to disengage and re-engage the four wheel drive. On the second attempt, the engagement lever felt different; somewhat free and smooth with little resistance. Up to that point, for the life of the tractor, it took a "firm" effort to engage or disengage 4 wheel drive. Definitely a difference now

I climbed under the beast and manually moved the 4 wheel drive fork/lever on the outside of the transmission and it felt free, but did have some resistance. I could not detect any binding.

The next day, no 4 wheel drive...

Has anyone lived through this problem? Solution?

By chance does anyone have the applicable pages of the maintenance manual for troubleshooting/repairing the problem?

Thanks in advance for your time and assistance.

Be safe and be well...

Chaos USMC

 

[pete-mi]

If this one is like the smaller models its likely the 4x4 shift fork. The end of the fork is in a sliding collar and the end has likely worn or broken off. On the smaller models you would need to drain down the transmission fluid. then unhook the rod from the lever and unbolt and remove the side cover this lever arm is fastened to. Replace the arm and seal and put it back together with the end of the arm in the center ring of the collar. . This hopefully is the problem as its a lot cheaper and you wont need to split the tractor to fix it. If not it could be a big repair.

 

[Chaos USMC]

Thanks pete-mi,

That is the consensuses. I have it in the shop now as I had a hip replaced recently and I am not ready to crawl under the beast yet. One thing my dealer said, when you shift into 4 wheel drive, use your loader (lower it slightly) to take some of the load off of the front tires before engaging or disengaging the 4 wheel drive. His reasoning; the gearing is not absolutely perfect and taking some of the load off the front wheels will ease the "transition" while engaging or disengaging. From a "mechanical" perspective, seems to make sense...

Thanks again.

Chaos USMC

 

[Chaos USMC]

Closing information.

Had the beast repaired, it was in fact the 4x4 front axle splined input shaft, it had rounded off. Guess it got that way from me trying to engage or disengage without relieving some of the drive-train strain, as mentioned above. When I went to pick it up, I did use the new technique and I could switch it in and out using two fingers, where before it took a fist full. All it took to repair was replacing that small section of shaft. Got lucky...