So just what kind of vehicle takes 6 quarts of oil? If you put 6 quarts of oil in any motor and it's gone there must be oil all over under the vehicle. It's not going to burn 6 quarts in a few hundred miles. Who the heck is playing with your motor? They don't have a clue what they are doing and you will be walking at the rate things are going! You put the motor oil in the transmission?

the major issue is all the oil is gone??? double check that its not leaking from the filter.. obviously u changed the filter im sure.... typicaly they gotta be decently tight and I like to put a lil oil around gasket before installing cause it actualy helps seal rubber gaskets believe it or not.... so check the filter... check the oil pan drain plug was reinstalled and is tight... as some one else said... if its smoking badly then you have more issues on your hands than u want. but since it over heated u could have issue with the head is leaking,. could be gasket or cracked... could be rings are shot.

the over heating issue can be water pump... or if it has a leak it might be leaking the anti-freeze out then over heating.. so if it has a leak find it... if not change water pump next since u changed the thermostat already... another unlikely possibility Is the radiator clogged up but that's not too common but it does happen.

friendly reminder.. WATCH YOUR TEMP GAUGE.. NEVER LET IT OVER HEAT.. IF IT STARTS TO THEN SHUT THE ENGINE OFF TILL IT COOLS DOWN CHECK YOUR FLUIDS AFTER IT COOLS OFF..

If your themostat is stuck closed it will over heat no matter what. Cheap fix. If your car is eating oil I woud ask are you seeing lots of smoke coming out of your tail pipe? are you dripping oil from the oil pan, or from a leaking gasket on your engine. You should have a huge oil spot where ever you park your car. Check your oil filter if that is loose it will leak. Good luck.

I'm guessing that you changed the oil filter, make sure the old filter O-ring wasn't stuck to housing. Gonna have to pressure-test the cooling system to find leaks, can rent that ( or borrow ) pretty cheap. Good luck!

Sounds as though car has major internal issues as you would have noticed any such large leaks externally. We likely have head gasket failure. Garage fix is best.

who knows

Can anyone help me? The car ran hot, so I changed the oil in my car, put coolant in, replaced the thermostat parked the car and the next day drove it 3 miles and it ran hot. All the coolant ran out and there was No oil in it after putting 6 quarts the day before. What should I look for or do to fix the problem?