Smart Roadster Auto Trans Grinding Needs Urgent Fix

Had nearly identical symptoms on my 2007 Smart ForTwo last year, rough shifting, grinding noises, and warning lights. Initial diagnosis revealed a failing torque converter, which was causing transmission fluid contamination. The transmission repair required removing the entire unit. The main issue was metal debris from the deteriorating converter clutch circulating through the system. Once opened, the technician found significant wear on the torque converter lockup clutch and damaged solenoids. The converter failure had already started affecting other transmission components. Complete repair included: New torque converter assembly, Transmission flush, Replacement of clutch solenoids, New filter and fluid This was definitely a serious repair requiring specialist knowledge. Not all shops have experience with Smart transmission systems. Would recommend finding a transmission specialist who specifically knows these units, as incorrect diagnosis can lead to further damage. The car runs perfectly now, but catching converter faults early is crucial. When these symptoms appear, continuing to drive risks total transmission failure. Based on your description, these are classic signs of torque converter problems that need immediate attention.

Thanks for sharing your transmission repair experience. My Smart has been running great since the fix, but curious how much you ended up paying for everything? The automatic transmission specialist I used mentioned these lock-up clutch failures are fairly common in our models after 100k km. Just wondering if you had any other transmission issues pop up since the repair was done? My mechanic recommended preventive fluid changes every 60k km to help avoid future clutch problems.

Thanks for asking about the costs. I ended up paying 2120€ for the complete auto transmission repair, which fully resolved the torque converter lock-up clutch defect. This included all parts and labor. After the repair 8 months ago, the transmission has performed flawlessly with smooth gear changes and no warning lights. The automatic transmission specialist did a thorough job fixing the converter fault, and I havent experienced any additional issues since. I definitely follow the 60k km fluid change interval now. Regular maintenance really helps prevent these expensive torque converter problems from developing. The transmission fluid condition can tell a lot about internal wear before major issues develop. The investment was worth it since the car shifts perfectly now. Just make sure to always use the correct transmission fluid spec, using the wrong type can lead to premature clutch wear and converter problems down the road.

Thanks for the advice. Finally got my Smart back from the transmission shop yesterday. The total repair came to 1890€ which included fixing the torque converter and flushing the automatic gearbox. The mechanic showed me the old parts, the lock-up clutch was completely worn out and had contaminated the transmission fluid with metal debris. He mentioned catching it early likely prevented more extensive damage. The car drives like new now, no more grinding or slipping between gears. The automatic transmission shifts smoothly and both warning lights are off. Really glad I took it to a specialist who knew these systems well. Going to stick to regular fluid changes from now on. The transmission tech explained how dirty fluid accelerates clutch wear, so keeping up with maintenance should help avoid another converter failure. Money well spent to get it fixed right.