A square deal ? part 2

So, I've been driving my car much more than usual, I went down for the inauguration, and then for Grandmom Luh's funeral, and now we'll be back down this weekend for Grandmom Smith's birthday. But coming back two weeks ago we got caught in horrendous traffic getting through the Lincoln tunnel, there was as accident involving two semis in the outbound lanes, which of course made them squeeze more cars in fewer lanes all around. When we finally got through the tunnel, one block later, my service engine soon light blared on again. And then my car didn't want to go past 30. I had my hands full with our superbowl party, then I got pretty sick, I didn't take my car back into the Auto Repair place until today. Where the guy insisted that it was not the transmission, but a ball bearing in the front left of my car that was not moving right and sending the wrong signals to the transmission. He plugged in the computer and it said that the 2nd gear was not right, but he insisted that the transmission was fine, and he showed me the transmission oil. I knew the oil would be fine, I just went to Jiffy Lube. BAH. So, now he's charging me $275 to replace the ball bearing and he said that it should be ready by 4 or so today. I just don't want that damn light to go on again, I honestly would rather pay a little more just to make sure it doesn't happen. So, we'll see. My Saturn has had a long life, let's hope she doesn't go the way of Pluto. Fingers crossed. One thing that I noticed driving it to the auto repair place today is that it didn't seem to have any problems going past 30, so maybe it's not the transmission, could this possibly be an honest mechanic?