Rear brakes seizing
 

1994 e320 18000 miles. The car has been sitting for awhile and now when I turn or back up, there is a loud noise, resistance sometimes up to actually preventing the car from moving. When this happens, the back end pulls downward, and the noise is loud. It sounds like the rear tire is stck...and sometimes when this happens gas leaks from the bottom. (maybe unrelated) Right now, it will not even move. HELP Please!!

at this point, it's anyone's guess. why not begin with a series of tests or changes if not
simply to eliminate possibilities. for example...

change rear wheels/tires from one side to the other
examine lug bolts to see if they are protruding out the back of the hub
did you do *anything* recently such as changing.....<fill in the blank> ?

since it only manifests itself during REVERSE, for that reason, I'm starting from rear

Seized brake
 

Thank you for you reply. I will do the things you suggested and let you know. We did have a flat on that tire, and had a doughnut tire on for a brief time. Also, this occurs in both forward and reverse driving. I was not very clear earlier, and I apologize.