D7E sprocket bearing question

drive the machine onto a block of wood to take all pressure off of the sprocket. remove the rear dirt guard and look on the top of the adjustment nut for the small rectangular key with a bolt in it. remove the bolt and then remove the key and with a pry bar in one of the notches in the adjustment nut turn the nut counterclockwise until tight. drive the dozer back and forth a few times and repeat. remember counterclockwise. i would also change the final drive oil and flush looking for metal in the oil. adjust the other side too.:tape:

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not sure of your serial number. here is a link to operators manual that should explain with pictures. if this isn't for your tractor just keep looking on that site until you find the correct manual.

Has anybody had any luck stopping the leak by tightening the nut or is the seal usually too far gone?
I think the SN is 75 E3. It's the third in the military numbers I know.

Early 75E's are the same as 48A6393 to 6882.
Chances of recovering the sealing are kind of slim and running loose sprocket bearings for long periods of time will take its toll on bearings. Tighten things up and hope for the best.

Has anybody had any luck stopping the leak by tightening the nut or is the seal usually too far gone?
I think the SN is 75 E3. It's the third in the military numbers I know.

[quote="DrewAbt"]Has anybody had any luck stopping the leak by tightening the nut or is the seal usually too far gone?
I think the SN is 75 E3. It's the third in the military numbers I know.[/quote]


I was able to solve a very small leak."just an occasional drip" on a D4 by tightening two notches.

So if I tighten the bearing how do I tell if the hub was loose and not damaged. Will it not snug up if the bearing is gone or going out?

can't hurt to try. or if you want you can pull it down and rebuild now or just run it to destruction. if you decide to try and adjust and want a little better idea of what is going on inside you can flush the final with some diesel and look for metal shavings. or get a borescope to look inside.

So I'm a little confused....if the inner seal is good and not leaking then I would only need to rebuild the outer bearing and leave the sprocket and final drive gearbox alone? Or does the whole thing need to come apart?