John Deere 506 rotary cutter service question

[tlary]

I just bought a 506 bush hog and would like to know how to change the oil in the gearbox. Where is the drain plug, what kind of oil, how much oil? The manual that came with it is useless, it only tells you how to check the oil level. I'm assuming that it uses 80w90 gear oil. I'm not sure if the big bolt in the center of the stump jumper is the drain plug.

 

[Tx Jim]

No oil drain plug. Either use a suction device or turn mower over on it's side.

 

[beenthere]

No drain plug, but don't think changing the oil is necessary plan.
If needing to drain, turn it up so it drains out the fill plug.

For sure it isn't the big bolt, as that just holds the stump jumper pan to the shaft.

Use GL-5 gear oil.

 

[Bigfoot62]

No oil drain plug. Either use a suction device or turn mower over on it's side.

A suction gun, like this:
301 Moved Permanently

 

[tlary]

Thanks, the oil is pretty black that's in it is pretty black, likely the original oil. What is gl5 oil? How much does it take also? Will 80w90 gear oil work?

 

[Bigfoot62]

Thanks, the oil is pretty black that's in it is pretty black, likely the original oil. What is gl5 oil? How much does it take also? Will 80w90 gear oil work?

Yes sir, 80w-90. The GL-5 is the API rating. See this: Gear oil - Wikipedia, the free encyclopedia

 

[tlary]

Well, I got the oil changed in it and it took about 16 oz. What a pain in the butt though with no drain plug. I would have thought John Deere would have done a better job designing that.

 

[beenthere]

Where would they have put the drain plug so you could get at it?

 

[jd870]

I have yet to see any drain plugs on gear boxes for rotary cutters on any brand i have worked with.

 

[Magicman710]

No drain plugs, but I've seen check plugs, usually half way up the gearbox to tell you how full to fill it. Most gearboxes only need to be 1/2 to 2/3 full, not completely up to the top.

The reason you usually don't have drain plugs is because you usually never have the change the oil. It doesn't get dirty and contaminated like engine oil. The original oil would likely last as long as the gearbox itself.