My 2006 Dodge Stratus keeps over heating.

Are the rad. fans coming on when it gets hot ? Has the mileage or performance dropped lately ? Seems you need a better mechanic , not being one yourself .

How many miles on engine now? Thermostat may need changing again. At the least someone with mechanical knowledge will need to inspect vehicle, it may be something simple or major. Pop the hood when engine is warmed up, and check at least cooling fans are turning on. If not, that could be why engine overheats. Again with engine running, squeeze radiator hoses (be careful of moving parts!) if they feel spongy, there may not be any coolant flow. That could be anything from a blocked radiator, bad thermostat, to bad water pump. Try enlisting some help locally, there's not a lot anyone online can do.

The car has 168 thousand miles. There is goop on the Thermostat. I have changed it twice . I also had it flushed 1yr ago.

well goop is never a good sign, as it may mean emulsified oil in coolant, and THAT may mean blown head gasket. "Block Tester" or a compression test may determine that. You'll need a professional diagnosis and start considering your options as this engine may be done for.

Just kinda Curious because I point this out wayyyy to much. I wonder if whoever worked on your car bled the system after doing major installs like that...

Air in your system causes freakin havoc. Personal experience.

Thanks for all the comments. I guess I may need to get it to a shop. Your comments have helped me a lot.