Ask the Mechanic

Ever Change This Oil?

(Progressive Farmer image by Steve Thompson)

READER: I have a 5103 John Deere tractor with 1200 hours on it. I have never changed the oil in the front-wheel-drive hubs on this tractor's mechanical front-wheel drive. I read that the hubs have John Deere hydraulic oil in them. How often should I change the oil, and how do I go about changing it?

STEVE: These outside planetary units are probably the most forgotten service area on a tractor. They have no way (except failure) of letting you know when the oil needs changing, but they usually just keep "rolling on." However, these units should have the oil changed after 250 hours of initial use then every 1,000 hours thereafter. To service the units, drive the tractor until the check/fill plug is at 6 o'clock. Drain the oil into a bucket after removing the check plug. A 1/2-inch ratchet and extension will remove the plug. Don't be surprised if you find small metal dust on the magnet on the end of the plug. Let it drain until there is only a drip running out. Next, drive the tractor until the plug is at 9 o'clock or 3 o'clock. Then, fill the cavity until the oil is level with the bottom of the plug. It holds less than a quart on this tractor. Finally, install the drain plug with thread sealer applied. Gosh, I think I just heard many readers say, "Wow, I have never changed that oil on my tractor."

> Write Steve Thompson at Ask The Mechanic, 2204 Lakeshore Dr., Suite 415, Birmingham, AL 35209, or email


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