Smoke from Axle

[Whitakerla]

So I'm new here and actually don't own the tractor. My mother owns a New Holland TN 60A FWD and runs an 88 acre farm. I live in Okinawa, Japan and can't be there to help her out. She was recently bush hogging when the left front axle (which I thought was a geared hub) started smoking. See image (the arrows were her idea) - that's where it was smoking from. She has greased every nipple that she can find, but I would assume that there's got to be some gear oil some where on the front axle (if they are in fact geared hubs). She turned it off immediately, let it cool down, and then test drove it again. There was no smoke. However, she has left it in the field to prevent any further damage. Does anyone know what could have possibly caused it to smoke and is it safe to drive back to the barn? Sorry for such vague details and any help would be appreciated. Thanks!

Lee

 

[k0ua]

The first thing I would do is check the fluid level in the front axle. Do I see wetness in the area of the arrows? Has it been leaking out? Yes the front axle has fluid in it. Most specify either the same fluid as goes in the hydraulic sump or 80w/90w gear oil. consult your manual. I would not move it until the fluid level was checked/refilled. You likely have at least seal damage that will need replacement, Whether the gears are heat stressed, I don't know. probably need a teardown and inspection. I will state I am no mechanic, but there are people on the forum here who are.

 

[Baby Grand]

Interesting configuration on that tractor:
New Holland TN60A Front Axle/Steering 1.40.0/02 FRONT AXLE - STEERING KNUCKLE - 4WD
Looks to have a double spider joint, but no gears where the smoke was noted.
Definitely have Mom check the oil level in the axle and look for leakage weeping seals.
Is it a very new machine or has it recently been serviced?
Just wondering if it never got filled from the dealer or missed after draining during service.

 

[Ed of all trades]

If she had noticeable smoke from the front axle I would say don't just add oil to the axle but it is time to replace the barrings on that end of the axle and check out the entire axle before small chips ect make their way to the gears and other barrings. Ed

 

[tcreeley]

Not the same tractor as mine. I have a NH TC30, but on mine the front axle is filled with the same hydraulic fluid that the rest of the tractor uses to run on. Gear oil-90lb I think will mess that axle up. Just stick with the right hydraulic oil. A slow leak or an empty axle could lead to some real problems. If it has to be driven- slow and easy, no 4wd.There probably is a fill cap with a dipstick attached along the top of the front axle.
Might want to check the bearing out. I've read that NH tractors sometimes requires rebuild of the bearings.
Goodluck.

 

[Gafn]

So was it smoke - or hydro oil mist when the axle was over pressure and vented?

Check the axle vent as well make sure there is nothing blocking it. (I did not see an axle vent on the diagram)
The flash point of hydro oil is 400 degrees F, normal operating temps should be around 110 - 140 degrees F

To get smoke there would need to be a lot of heat in that axle, if indeed it was smoke - I would replace all the fluid, might even tear down that side to inspect the bearings like tcreeley stated.

Ask your Mom if she remembers touching the axle after shutting down the tractor - was it warm, or hot... it is was just warm - normal - it was most likely an over pressure out gassing that had hydro must in it....