JD 770 4X4 leaking oil from front wheel

Shady Acres · Jun 21, 2007

Has anyone had to deal with gear oil leaking from the front axle on their 4X4 tractor? The inside of my front right front tire has become covered with oil & dirt and it is starting to leave a small puddle of oil on the ground when parked for any amount of time. I have not had a chance to pull the wheel and perform a closer inspection, but since the oil does not show on the vertical part of the axle that runs down to the hub, I am thinking it must be leaking down at hub itself.

My I&T shop manual shows a seal located behind the hub that the rim bolts to. I have gone to my dealer and purchased this seal along with a wear shim also shown in the same area (almost falling over when the bill came to $64 for these two parts) and plan on "tearing" into the repair this weekend.

I was some what surprised that the seal the dealer provided did not seem like anything more than a grease seal I have seen on trailer and car wheels so I am wondering how this will hold back gear oil? I am also wondering if the wear shim is an integral part of the seal or if I can re-use my old shim if an inspection seems like it is o.k.? (it would be nice to get $36 back for the return of the new one). I guess I'll know more once I actually get things disassembled but I figured I would at least take a stab at having the replacement parts on hand.

If anyone has been through a similar repair on their 4x4 I would appreciate any tips or insight you may have.

Thanks in advance.
Jay

dfkrug · Jun 21, 2007

I have replaced seals on a JD955, which may be similar.
It was quite easy.

You might find that oil leakage is less or non-existant if you
store the tractor with plenty of weight on the front axle. I
found that I could make non-leaky axles leak by putting the
front end on jackstands over night.

Anyway, you can use RTV silicone instead of the paper gasket
when you put things back together.

As it turned out, the first seal I replaced was OK; it just had some
nylon fishing line caught in it. I did not need the new expensive
seal.

Soundguy · Jun 21, 2007

Be carefull about replacing gaskets with go.. While I don't have your manual.. some gaskets control bearing preload. Perhaps not in this case.. so it may be irrelevant.

Also.. any time I see a seal leaking.. I always check the bearing play.. leaky seals can be a sign of a worn bearing.

Jack the front end up and see if the hub wabbles / has play..

Soundguy