It is very important to check your gearbox oil on your power barrow, both when the machine is new and regularly through its life. Note the picture the left shows the gearbox oil level bung. Oil should just dribble out slowly if correct.
If you need to add oil remove one of the rubber filler caps on the top of the gearbox. Add the oil slowly until it runs out of the level bung. Ensure you reinstall the rubber cap correctly.
Always have your tracked dumper on level ground when your check your oil level.
The MD500H-Pro mini dumpers uses 1.5L of EP80/90