Ok so I'm new to this I bought a few months ago a 2011 RA
It has a 3" cat back exhaust magnaflow
About 3 days ago I had been driving for about 30 min and went to back into a parking spot when I put the car in reverse I got the
Transmission overheat
Slow down message
Then as it went away the service transmission required warning came up and the car went into limp mode and wouldn't go anywhere I turned the car off for a min then restarted it and it just gave me the service transmission required but drove just fine now it is doing it every time I drive it so I haven't drove it in a couple of days it only has 84k miles any advice please help

 

Take it to a Mistsubishi Dealership for service.

 

Yeah, bring it in. Do you know the last time the transmission fluid/filter were changed and with which products?

 

Hi kraken2011,
I have had similar problems with my 2011 RA, but only when I am on the track for more than 20 to 25 minutes or in the 2nd or 3rd run sessions of a track day. I have changed tranny fluid with approved Mitsu fluid twice and installed an AMS upgraded tranny cooler. However, neither has helped much. I have never had it overheat on public roads; only on the track. Perhaps that is a problem with all automatics under heavy usage. Thinking about diverting additional airflow to the tranny area.

 

It may be a simple as a bad temp sensor. Again, the Mitsu dealership is the place for a problem this complex.

 

I had a similar issue and ended up having the valve body replaced under warranty