I have a 2009 Explorer automatic with 205k miles, never once slipped or leaked any fluid. Drove normal last night, when I got in it this morning and put it in drive it moved a few feet and wouldn’t drive I put it in park and had a huge fluid leak under it. There was no leak in the driveway where it was previously parked before moving the few feet. I did find in the puddle a large snap ring I assume it has something to do with the transmission instantly leaking all its fluid. My question is anyone have any ideas of what would possibly cause this? With its age and miles I wouldn’t want to put a transmission in it and if it’s a obvious issue I would prefer to avoid towing it somewhere and paying for them to tell me it needs a new transmission. Thanks for any thoughts!

 

There is a good possibility a piston was allowed to move further than where the lock ring holds it..
The piece could be on the ground or maybe stuck part way in the side of the trans.. Look underneath the vehicle and see if you can see the opening.
This will require a tow to a trans shop to reinstall a new lock ring and any parts that may have been blown out.
Not much choice here.