L4400 front axle leaking. GRRRRR!

[HEC]

Thanks for these posts everyone, I have learned some new things today .

 

[Greenfield Dave]

Filled it up with 75w-90 Synthetic Lucas oil. $45 a gallon, but still cheaper than new bearings!!

 

[PapaPerk]

<img src="http://www.tractorbynet.com/forums/files/kubota-owning-operating/387200-l4400-front-axle-leaking-grrrrr-140819_0001-jpg"/>
Well, I'd say it was the bearing!! It took the seal with it, and scratched the heck out of the axle too! I only worked about 2 hours after I noticed the leak. But I must say, it was pretty easy to replace.

Looks like my L3830 failure. I think my seal failed which caused the bearing to fail....

 

[Greenfield Dave]

That would be my guess, but we will never know which failed first. I'm just glad the damage was contained between the ring gear and the housing. Otherwise the debris could have made it's way to many more bearings...

 

[buck boost]

Good doing Dave - failures like this are pretty uncommon and usually start with a metallurgical defect in the bearing from new. A defective ball starts to break, damaging the race, eventually jamming and shattering, then another fails because the race is rough, the spreader breaks, and on and on until it runs loose enough to make the seal leak. With the bad parts replaced, you could go right back to doing whatever you were doing and it would almost certainly never fail again. Bearings are made in huge numbers and defects are so rare they probably don't even inspect them. Just bad luck to get a bad one.

1,000,000 % truth right there ^^.

And just another reason to NEVER "tap on" or "beat on" a good bearing. Always use a press or puller. When mechanics beat on bearings, or use impact guns on a axle nut through a hub, it has a high potential to pound the inner and/or outer race causing a very, very premature failure.

Looks like my L3830 failure. I think my seal failed which caused the bearing to fail....

Unless the seal allowed a contaminet into the bearing, it was probably the other way around. Typically, seals fail (leak) for two reasons. Old age, or a wobble effect due to another part failure.


I highly doubt the bearing/seal failure was related to the lubricant in front axle of the OPs tractor. Heck you could probably use olive oil in the front end and it would last longer than that (with a "good" bearing.

Just for kicks, I just looked up how many revolutions per mile my pick tires turn. I replaced both sealed hub assemblies at 100K miles because one was howling. 685 revs per mile X 100,000 miles = 68,500,000 revolutions. And those are sealed units that operate at a much, much higher speed. I replaced both just because, but one was still good.

How many revolutions on the L4400? No idea, but way under 68 million. Defective bearing? Yes. lol

"New means new, not good".

 

[PapaPerk]

1,000,000 % truth right there ^^.

And just another reason to NEVER "tap on" or "beat on" a good bearing. Always use a press or puller. When mechanics beat on bearings, or use impact guns on a axle nut through a hub, it has a high potential to pound the inner and/or outer race causing a very, very premature failure.

Unless the seal allowed a contaminet into the bearing, it was probably the other way around. Typically, seals fail (leak) for two reasons. Old age, or a wobble effect due to another part failure.

The metal retaining spring in the seal failed... Separated and ended up getting into the ball bearings causing them to wear out.

Did you work on my tractor? Didn't think so. (0:

 

[N80]

Bump to an old thread: My L4400 right front axle case started leaking around the pivot point. I read all the DIY threads about this and decided against doing it myself. But I did remove the case itself and took it to the dealer rather than sending them the whole tractor. They replaced the large top seal at the pivot point, the seal cap at the bottom, the big o-ring on the bevel gear and the o-ring for the case assembly itself where it meets the axle tube. The cost was $245 which I thought was very reasonable. I do not know how much more it would have cost if I'd just take the tractor in but the dealer just said "a good bit more" and seemed glad not to have to deal with the tractor.

To get the unit off you have to remove the 4 case screws and the tied rod end. The shop manual says to pop the tie rod end out with a special too. I did not do that and just unscrewed the tied rod at the grease seal. Quick and easy. You just have to make sure your toe-in is correct when you put it all back together.

Getting the case loose was a bit of a chore. Not sure why but it took a lot of prying, pulling and banging. It is heavy. Not unmanageable but quite awkward. I had a chain hoist at the ready but did not need it. I was able to get it back on by myself (no helper). Also a bit awkward as the axle splines have to line up. Also be aware the the axle will pull right out of the diff. Its no big deal, you just put it back in.

Anyway, that's how I got it resolved. (Of course it has been leaking for over a year and I just now got around to it. During that time I kept the axle full of 85-140 gear oil. Thick as syrup. Fortunately all internals and bearing still looked pristine.

 

[sixdogs]

N80--great info. Thanks.

 

[repete]

This used to be a regular event when I had my front wheels set to the widest position. I still have a complete set of pivot seal, inner and outer bearings and seals on the shelf collecting dust now. When the wheels were set wide, all of the load was on the smallest outside bearing. Also cracked housings due to the the out of whack load path. Have had no issues for the past couple thousand hours or so on the L2550DT after going back to narrow. Tractor is now sitting at about 5500 hours.