Automatic Trans not upshifting to 4th
 

I have my car since Nov 1st so far i love it but today I had something wierd happen and wanted to know if anyone else is haveing this problem. I was driving the car and it stayed in 3rd and wouldn't upshift. I am bring it to the dealer tomarrow but wanted to know if anyone else is having this problem or does anyone have a suggestion on what to do. The fluid level is ok but i do think i hear a rattling now but i might be noticeing a sound that was there already but i hear it now because of haveing troubles.

TheJoker:

What speed where you at when you tried upshifting to 4th? Did you use the manual shifter, right steering wheel paddle, or left steering wheel paddle? I have never had a problem upshifting using either method, but knowing which one didn't work for you would help in diagnosing the problem.

It does it in auto mode only I don't have any problem shifting in manual mode all gears work but it does "stick" in 3rd in auto mode. I don't think it matters what speed in auto mode it should always go into 4th when you are off of the gas, right?