LT50 FAB Transaxle Trouble

[SpaceCadet]

Hello all,

First time posting here and am in need of the cub cadet experts in the room.

We have a 2021 LT50 FAB with 70 hours that recently started having issues with its drive. Nominally when you let your food off the fed/rev pedal the hydrostatic drive would slow you down. In our case the mower would make a clicking sound and continue to roll. This was more pronounced when going down an incline and you would have to use the brake. Thought the free wheel lever was out partially so ensured it was in and same issue. It did seem slower overall, but didn’t lack power as it still would climb hills.

Recently started making grinding noise when pedal was down all the way. Now I’m trying to find out if the transaxle is bad or if possibly the drive belt/idler/tensioner are bad.

I jacked up the back and ran it in fwd and rev. Stopping one wheel allowed the other to spin and vice versa. Seems diff is ok. Wheels have a bit of play, but didn’t seem out of the norm.

Weird thing is I can push the tractor fairly easy even with the bypass lever in the drive position.

I am planning to replace belt and pulleys, but am worried it’s the transaxle itself.

Any advice would be appreciated!

[ironman]

Start with the easy stuff before belts and pulleys.
Your foot control, through linkage and rods move a thing in the transmission called a swash plate.
Your "free wheel lever" operates a valve inside the transmission called the bypass, again through linkage and rods.
I would get under the tractor and inspect all the places where both controls operate.
Look for grass clipping build-up or debris that may not be letting controls operate completely as they should.
Remove the deck for better access and blow it all out with compressed air.

[SpaceCadet]

Appreciate the input! I will do some more investigating tomorrow and will report back what I find.

[SpaceCadet]

Had a chance to do some more troubleshooting as ironman suggested above.

Inspected all linkages including pedal linkage to trans and bypass. All were free of obstructions and freely moving. Moved the pedal in fwd and rev and action back to trans looked smooth. Brake mechanism checks out as well.

I had the new drive belt already so went ahead and swapped it out. Pulleys all looked good, no flat spots and spun freely. Trans fan is intact and pulley didn’t appear to have any play.

Started it up and same issue. It would barely move now in both fwd and rev. The further you push the pedal down the more vibration from the back end. If you pull the free wheel lever out the same sounds/vibe is present.

Open to any other ideas.

Neighbors had their cub cadet (same year just a 46 instead of 50) in for repair because trans went out. How common is a transaxle failure?

[ironman]

It looks like your tractor's transaxle is a Tuff-Torq K46.
It is a low end transaxle meant for light duty (i.e. mowing, not plowing or pulling).
They do seem to have a high failure rate, but that being said there are probably more of them out there than anything else so maybe it just seems high.
The good news is that they are repairable, the bad news is it ain't cheap, even doing it yourself.
If you are inclined to do that, watch this video. It will show you what you'd be up against. I have done a few of these and this video is excellent.
https://www.youtube.com/watch?v=K9zgAhpyFwM

[SpaceCadet]

Sorry for the delay! Thank you for the info and video link. I watched it and think I’m going to tear it down and see what all is damaged.

Even if it’s fixed not sure how long it will last for the next round. Might need to look for something that has a beefier transaxle. Not sure if the hydro gear ones on zero turns like the ZT1 are any better.

[Sam Mac]

Maybe you can adapt one of these into the tractor

https://www.surpluscenter.com/Brands...le-13-1632.axd