Can I put tractor gearbox oil in a 2 stroke Tomos ATX 50c moped?

You could. But shouldn't. It's not the same stuff.

If you are talking about the moped final drive, it's going to take something like 80/90 weight gear oil.

That oil is probably more akin to Dexron ATF fluid. It will likely be ok for auto boxes, hub reduction with wet brakes and such, but will be too low a viscosity for the comparitively primitive scooter.

Consider that although short term it might seem ok, long term you would risk increased wear. It might even leak past the hub seals when it's hot, then the back tyre will be covered in oil. It's not worth the small cost saving.

Check the manufactures specifications, but I doubt the JD stuff is what you're looking for.

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