When you drain your oil, try to drain it into a clean container, then push a magnet around in the bottom. As above, carefully check your pre-drain oil level. And save a sample for an oil analysis, will tell you how much gas is in oil, and other contaminates. Look up Blackstone for their oil analysis kit. When I recently did an engine-out rebuild of my truck and the sheet metal as part of my restoration, I decided I would use a block off plate for the mechanical oil pump, having heard about the high risk failure of the sea mostly due to age and modern gas, with a 24 V Facet electrical pump. Even had my stock mechanical pump rebuilt to modern standards. It sits in a box now.
I know how sick and worried you must feel now. At the least, you will need to clean out your oil filter too. It is not too hard to pull the sump pan from below, and replace the bearings and seals, and at least do a visual inspection of the crank when you can see it. If you have hurt your motor, it can be repaired or even perhaps rebuilt to a better than new standard. I did my restoration in my garage and driveway. Took time and money, though. I suggest you do a search on the other M37 forum, lots of pictures and experiences with what may be necessary. I would't try to start the motor until this is sorted out. These trucks have forged cranks, so the steel is pretty tuff, and the bearings are designed to take the wear first.
Try to keep some hope for your motor, and remember, if necessary, it can be fixed. Start looking over what and how to do this on:
http://www.g741.org/PHPBB/
let us know what you find.
here's hoping..... NAM VET
