Greetings; I was brush-hogging my field for about an hour when the engine started making a noise, so I shut it off immediately. I got off and inspected and did not see any issues. The oil on the dip stick was at the low end of the operating range, but in the range. I started the engine briefly and there was zero oil pressure so I shut it off. About 15 minutes earlier the front wheels dropped into a hole that was hidden by brush. The loader on the front caught the drop in the front end, and I used the loader to lift the front and back the tractor out of the hole. I did not see any damage to the tractor so I continued brush-hogging the field, which is mostly grass and wild flowers in that area. A friend plans to help me tow the tractor out of the field in the next few days. Any thoughts on what I should do/look at when I get the tractor out of the field?