Diagnosing Tractor Bad Sound

[mmranch]

Thanks again for the ideas.

Yesterday, I pulled the tractor out of the shop and raised the front end off the ground with the snow plow. Turned off the engine and spun the front wheels by hand and listened/felt. Both wheels spun just fine with no binding or bad sounds at all. I could faintly hear the internals of the axle spinning as I spun the wheels. Resistance was consistent on both wheels with no problems heard/felt.

I was also thinking that if the front axle had a problem, such as a bad bearing out near the wheels, it would have to be a very bad bang to transmit through the axle to the frame and all the way back up into the cab for me to feel it. When the noise/feeling happens it feels like it's coming from underneath me like the transmission or chains hitting... but there are no chains hitting. It's kind of like when a U-joint goes bad on your car driveshaft... in most situations, the car drives normally, but in certain situations you hear/feel a clunk-de-clunk-clunk. Except there are no U-joints on the tractor.

After spinning the wheels, I got a pen and paper to take notes and proceeded to carefully start doing some plowing around the shop. I had my headphones on but no music playing so I could really hear the tractor. At first, I plowed in L4 going forward and reverse with no real snow load on the blade. Did this in 4WD and 2WD. For about 15-20 minutes there was no problem. Then the problem sound happened for a few moments then stopped. I changed to M1 and drove over to the house to plow there. No problem sounds as I drove over. Then plowed a bit in M1 and M2 and heard a couple of moments of the sound but then it would stop. Proceeded to plow big snow by the house in L1, L2, L3, L4 and didn't really hear the sound except for a couple brief moments. This took about an hour. I will have to carefully monitor the situation to try to find some pattern but it's very intermittent.

I need to get some more gear oil then I will change all the oil in the front axle. When I drain the front axle, there is always metal in the oil. But it's very fine and you can see it sparkle in the oil. I will be looking for more metal than normal and big chunks to see what may have happened inside.

It's definitely a puzzling problem.

Thanks again.

 

[crashz]

Can you get the tractor in the garage and jack up the rear? I would want to get it solidly on jack stands and spin the rear tires by hand. Be careful jacking it up as the front axle pivots, so it won't give any lateral support. In fact, I like to lift the front with the loader bucket and block from there as it stabilizes the tractor a bit better.

The inconsistency seems like it could be something other than driveline. Chains, or something else hitting the body seems more likely. Even a loose or jammed cab mount or something jammed in between the cab and frame??

I have tendency to think the worst when I have a nasty sound. I have usually killed and buried the engine or trans, when some minor issue is the real cause.

 

[loggin]

Thanks again for the ideas.

Yesterday, I pulled the tractor out of the shop and raised the front end off the ground with the snow plow. Turned off the engine and spun the front wheels by hand and listened/felt. Both wheels spun just fine with no binding or bad sounds at all. I could faintly hear the internals of the axle spinning as I spun the wheels. Resistance was consistent on both wheels with no problems heard/felt.

I was also thinking that if the front axle had a problem, such as a bad bearing out near the wheels, it would have to be a very bad bang to transmit through the axle to the frame and all the way back up into the cab for me to feel it. When the noise/feeling happens it feels like it's coming from underneath me like the transmission or chains hitting... but there are no chains hitting. It's kind of like when a U-joint goes bad on your car driveshaft... in most situations, the car drives normally, but in certain situations you hear/feel a clunk-de-clunk-clunk. Except there are no U-joints on the tractor.

After spinning the wheels, I got a pen and paper to take notes and proceeded to carefully start doing some plowing around the shop. I had my headphones on but no music playing so I could really hear the tractor. At first, I plowed in L4 going forward and reverse with no real snow load on the blade. Did this in 4WD and 2WD. For about 15-20 minutes there was no problem. Then the problem sound happened for a few moments then stopped. I changed to M1 and drove over to the house to plow there. No problem sounds as I drove over. Then plowed a bit in M1 and M2 and heard a couple of moments of the sound but then it would stop. Proceeded to plow big snow by the house in L1, L2, L3, L4 and didn't really hear the sound except for a couple brief moments. This took about an hour. I will have to carefully monitor the situation to try to find some pattern but it's very intermittent.

I need to get some more gear oil then I will change all the oil in the front axle. When I drain the front axle, there is always metal in the oil. But it's very fine and you can see it sparkle in the oil. I will be looking for more metal than normal and big chunks to see what may have happened inside.

It's definitely a puzzling problem.

Thanks again.

Like crashz said. I also might try putting all fours in the air and spin the wheels. Make sure you have it properly secured!! Also was wondering if your front drive shaft is a splined shaft where the coupler is warn to the point of skipping teeth. I know this can happen on Kubotas and it does make quite a concerning noise.

Hope this helps!!

 

[Williy]

With the chains on the inside of the wheel
look for a loose end {have tractor wheel off
the ground] and then holding the loose end
turn the wheel and see where the loose end
is touching

willy

 

[nyone]

. When I drain the front axle, there is always metal in the oil

I would say theres a clue. Did you check the hub oils?

Dont bother jacking it up and trying to turn the wheel by hand. It sounds like it dosnt happen alot and I bet you dont want to be pushing the wheels over for 30min.

Are you sure your tires front/back are the correct size?

 

[mmranch]

Thanks again for the ideas.

I will be jacking the tractor up and checking the wheel spin on the rears and the front drive shaft and chains. The shaft is splined and I've replaced before it because of worn splines. But since the bang sound happens also in 2WD (when it happens) I'm not sure if it's logical that the front drive shaft would be causing the sound... but it might.

Not sure what hub oils are. When I drain the front axle, there are two plugs out by the wheels at the bottom and one plug under the middle of the axle. I drain all three plugs. There is usually very fine metal particles in the oil to some degree. Always has been and you can see it floating in the oil in the pan... this has been normal for years. I will be looking for more than normal metal and larger particles. But I still need to go to town to get some more oil first.

Yesterday, I plowed for an hour and only heard the sound a couple of times for a brief moment. Here's a picture of some plowing yesterday.

Today, I've got to use the tractor to pull ice dams off the roof.

Thanks again.

 

[nyone]

Typicaly the front center section will have it's own oil level and each drive hub will have there own. Are you checking all 3 spots?

 

[mmranch]

Thanks for the info!

This front axle only has a single oil level and fill hole which is to the left of center on the axle top. When filling the axle, it takes time for the oil to make it's way to the bottom of both hubs, then you have to top it off again.

Thanks again.

 

[frogpond]

Perhaps universal joints on driveshaft to front axle? Had similar symptoms on my little Kubota, and that's what it turned out to be. Replacement was easy and cheap. But you have a different tractor. Have you searched to see if others with your model have dealt with the same symptoms?

 

[frogpond]

Oh, sorry. I just read that you have no u joints.