Torque Converter lockup stuck off

I was told by Auto Zone that my torque converter lockup is stuck off. I have a 2005 Chevrolet Impala. Is this serious?


sorry misread,milage ? engine size? troble code.?

It has about 90,000 miles. I don’t know the other info.

How do they know? Is this based on a code reader?

It is best to get the actual code and post it, but often having a code that indicates a TCC (torque converter clutch) problem just means that there was a problem - not necessarily that it persists. So, depending on the code your TCC might not be stick “off” - but it was at some point.

It is “serious” in the sense that a major part of transmission operation is showing an issue. But it isn’t instant death, and as far as I know one can disable the TCC system in many cars and still drive around quite happily. What it will mean is that at cruising speeds your engine will run a bit faster (more rpms and somewhat lower fuel economy) and your transmission a bit hotter. The latter is bad in the long run since I have been told that the big killer of the transmission is heat. Basically, at steady speed and in top gear, there is an auto clutch that will lock your engine and tranny together to run at the same speed. Just Google it and you’ll get plenty of good explanations of what the TCC is and does.

My car is completely different ('97 Escort / 210K), but I have had TCC codes on and off for the last 60-70K or so. I think that I’ve determined that it sometimes won’t kick of when I need more torque going up hill - but I could be completely wrong. At any rate, mechanics give me that “you’re an idiot” scoff every time I mention it, but I dropped my transmission pan/filter a couple of times within about 10K miles of each other and my TCC codes went away - clean fluid won’t repair an actual mechanical problem, but it surely doesn’t hurt. TCCs are often (always?) controlled by a pressure switched solenoid. I assume that mine was a bit gummed up or something. So you could try the same - especially if you haven’t regularly serviced the tranny.

It might be as simple as the brakelight switch. If it fails the lockout converter will not work.