Problem kubota 4 wheel drive

[cowgirl]

Sorry, I was trying to clarify what you said about couplers. To help the poster understand. I now know that there are no U joints. But there should be from the factory.

I don't associate the term "couplers" into driveshaft terminology. No matter what K calls them. It's a slip joint in mechanical terms.

Overall, it's a relatively sound design except for the fact that frames twist under load. And that's what causes the splines to disintegrate over time. In my opinion, K should have put in constant velocity or U-joints. with a mid point slip joint.

Bottom line, I see what you are doing and am trying to figure out a solution. I'm thinking driveshaft - shield misalignment, but pictures would help.

The inside of the front coupler looks exactly like the photo in video #8..could the problem be I only replaced the damaged one going into the front shaft as the rear coupler did not show any damage leaned and greased both couplers and splines on the shaft

 

[North Idaho Wolfman]

Exact model is a M8540HD
With the tractor in 2wd, lift both front tires off the ground.
Hold one tire from turning and spin the other in both directions.
do the same for the other
Listen for noise and binding.
Sadly, I'm betting you have a damaged front diff, most likely the ring and pinion, as it has a helical cut gears and you would get a different sound out of it going forwards and backwards.

 

[cowgirl]

Exact model is a M8540HD
With the tractor in 2wd, lift both front tires off the ground.
Hold one tire from turning and spin the other in both directions.
do the same for the other
Listen for noise and binding.
Sadly, I'm betting you have a damaged front diff, most likely the ring and pinion, as it has a helical cut gears and you would get a different sound out of it going forwards and backwards.

Did that with both front tires in 2 eheel drive one at a time they both spin freely forward and backward no binding or noise
When doing the same procedure the tires locked

 

[cowgirl]

Did that with both front tires in 2 eheel drive one at a time they both spin freely forward and backward no binding or noise
When doing the same procedure the tires locked in 4 wheel drice

 

[RCW]

When doing the same procedure the tires locked in 4 wheel drive.

They should, as the propellor shaft/driveline is preventing their movement.

No sounds/problems rotating the wheels in 2WD is important.

IN 2WD, when you spin one wheel, does the other turn in the opposite direction?

When you say it "howls like a coyote," where can you best describe where the howl is coming from?

Is it in the front of the tractor, or in the middle, or toward the rear of the tractor?

 

[cowgirl]

When doing the same procedure the tires locked in 4 wheel drive.

They should, as the propellor shaft/driveline is preventing their movement.

No sounds/problems rotating the wheels in 2WD is important.

IN 2WD, when you spin one wheel, does the other turn in the opposite direction?

When you say it "howls like a coyote," where can you best describe where the howl is coming from?

Is it in the front of the tractor, or in the middle, or toward the rear of the tractor?

When I lift the front-end while in 2 wheel drive and manually rotate the left front tire the rt front tire moves in the same direction but slowly
I will have to figure out how to listen where the sound is coming from as it only makes the sound when moving in 4 wheel drive any suggestion without walking along side of moving tractor
Thanks

 

[cowgirl]

When I lift the front-end while in 2 wheel drive and manually rotate the left front tire the rt front tire moves in the same direction but slowly
I will have to figure out how to listen where the sound is coming from as it only makes the sound when moving in 4 wheel drive any suggestion without walking along side of moving tractor
Thanks

The sound when walking along side then standing on the foot stand the sound seems to be coming from near where the shaft goes into the housing
Sound is not as loud now but not normal

 

[cowgirl]

The sound when walking along side then standing on the foot stand the sound seems to be coming from near where the shaft goes into the housing
Sound is not as loud now but not normal

Middle of tractor not front or rear

 

[North Idaho Wolfman]

When I lift the front-end while in 2 wheel drive and manually rotate the left front tire the rt front tire moves in the same direction but slowly

That would be normal on that model as it does have a limited slip differential.

 

[North Idaho Wolfman]

Check the rear connection of the the propeller shaft cover.
If nothing looks off, pull the covers off and see if there is still a noise.

 

[cowgirl]

Check the rear connection of the the propeller shaft cover.
If nothing looks off, pull the covers off and see if there is still a noise.

View attachment 113451

Crap
..just tried ...now I can not get the shaft off the the front going into axel back of the shaft neat Trans moves but the front now will not move..

 

[North Idaho Wolfman]

The two cover tubes slide inside each other, and if they won't then there is probably where your noise is coming from.

 

[cowgirl]

The two cover tubes slide inside each other, and if they won't then there is probably where your noise is coming from.

No it is the coupling.
Tried to drop the shaft to try and align the 2 screws thinking it might be a balance issue now can not get the shaft out the back coupling is free but the front one will not move

 

[North Idaho Wolfman]

No it is the coupling.
Tried to drop the shaft to try and align the 2 screws thinking it might be a balance issue now can not get the shaft out the back coupling is free but the front one will not move

With the roll pin out you can tap the coupling on the side to get it to move.
It's sounding like it might have tried to spin it in the splines.
You can remove the rear coupling and pull the shaft out that way.

 

[cowgirl]

With the roll pin out you can tap the coupling on the side to get it to move.
It's sounding like it might have tried to spin it in the splines.
You can remove the rear coupling and pull the shaft out that way.

Tried both there is not enough room to pull the shaft removed both roll pins tried prying with large screwdrivers coupling on on the pinion gear will not move enough to release the shaft

 

[North Idaho Wolfman]

Tried both there is not enough room to pull the shaft removed both roll pins tried prying with large screwdrivers coupling on on the pinion gear will not move enough to release the shaft

Sounds like you've twisted the coupling on the shaft, you can try and use a pipe wrench to turn the propeller shaft to just the coupling loose.

If you can't then things get interesting, like removing the front axle interesting.

 

[cowgirl]

Sounds like you've twisted the coupling on the shaft, you can try and use a pipe wrench to turn the propeller shaft to just the coupling loose.

If you can't then things get interesting, like removing the front axle interesting.

Just my luck...will try in the morning have to feed the try and get the black grease off ran out of nitrile gloves..when I use the pipe wrench.what to try and protect the shaft and there seems to some play in the pinion gear
Thanks for your help

 

[cowgirl]

Just my luck...will try in the morning have to feed the try and get the black grease off ran out of nitrile gloves..when I use the pipe wrench.what to try and protect the shaft and there seems to some play in the pinion gear
Thanks for your help

Do you have a schematic of the pinion assembly and the 2 bushings .mounting brackets that secure case to tractor.
Thanks

 

[cowgirl]

OK Wolfman how do I go about replacing the pinion gear

 

[NorthwoodsLife]

Hold on cowgirl!
You'll have some play in the pinion end.

Get the shaft and it's sleeve off, and use tractor in 2wd. Check for noise.

Then try it with shaft on only without the sleeve, in 2wd and 4wd. Check for noise.

Did you use new roll pins?