Grinding Shifts? Impala's Torque Converter May Be Failing

Had a similar problem with my 2011 Chevy Malibu. The symptoms matched yours exactly, rough shifts, grinding, and transmission warning lights. After some investigation, it turned out to be a faulty lock-up clutch in the torque converter. With some experience working on cars, I first thought it might be just a transmission fluid issue, but the automatic gearbox symptoms got worse. My regular workshop confirmed the converter failure through diagnostic testing. The complete repair included replacing the torque converter and some related components to prevent future engine surge issues. Total bill came to 2120 Euro for parts and labor. The repair took about 3 days, but it fixed all the transmission problems completely. Before suggesting more specific advice, could you share: Current mileage? When did you last change transmission fluid? Does the problem get worse when the engine is hot? Any specific error codes from your scan? These details would help identify if you're facing the exact same transmission repair issue I encountered.

Thanks for the helpful reply. My Impala has 138670 KM on the clock and just had a service last month, including fresh transmission fluid. The auto transmission problems do seem to get worse after driving for about 20 minutes when everything's warmed up. The scan showed code P0741 which points to the torque converter clutch solenoid circuit malfunction. Based on what you shared about your repair costs, I should probably start setting aside some funds. Good to know repairs fixed things completely in your case.

Yeah, that P0741 code on your Impala matches exactly what I saw with my Malibu. The lock-up clutch issues definitely get more noticeable when the transmission heats up, which explains why you're seeing worse performance after 20 minutes of driving. Even with fresh transmission fluid, when the converter fault is present, the automatic gearbox will continue acting up. The fluid change likely ruled out any simple maintenance fixes, so we're probably looking at the same torque converter replacement I needed. My repair experience post-fix has been great, no more engine surge, clean shifts, and all warning lights cleared. The transmission has been solid for about 45000 KM now since the repair. Just make sure whoever does the work includes a thorough flush of the transmission system when installing the new converter. Small metal particles from the failing clutch can circulate through the auto transmission and cause problems later if not properly cleaned out. The price I mentioned earlier included that full system flush along with the new torque converter assembly. Given your similar symptoms and error code, you're likely looking at comparable repair costs.

Thanks for the detailed information about your repair experience. The P0741 code and symptoms matching your situation really helps confirm what I'm dealing with. Since my transmission fluid is fresh and the problems are still there, especially after warming up, I'll start planning for the torque converter replacement. I'll make sure to ask the shop about doing a complete system flush too, good point about clearing out any metal debris from the automatic gearbox. Getting this fixed soon makes sense since I don't want to risk more damage to the transmission. I'll start calling around for quotes and check if any shops can match or beat the repair costs you mentioned. At least I know what I'm getting into now with both the repair process and expected price range.