Mercedes GLA transmission issue

Converter fault on an automatic transmission, huh? Sounds familiar. I had similar symptoms on my GLA. Grinding noises and the transmission slipping are classic signs. The lock-up clutch could definitely be the culprit if your mechanic says so. Did he check the transmission fluid level and condition before jumping to the torque converter?

He did mention the fluid looked a little dark, but he seemed pretty sure it's the torque converter itself, especially the lock-up clutch. Is it possible the dark fluid caused the converter to fail, or is it more likely the other way around? And is that price reasonable for a transmission repair like this?

Dark fluid could contribute, but it's more likely the converter fault contaminated the fluid. As for the price, it's hard to say without seeing the breakdown, but converter replacement is involved work. Definitely take it to a transmission specialist for a second opinion before committing to the work! You need to get a better idea if they are certain about the converter fault, or if they're just guessing.

Thanks for the advice! I took it to a transmission specialist as you suggested. Turns out it was indeed the torque converter lock-up clutch. They confirmed the diagnosis and the price was pretty much the same. Got it fixed and it's running like new. Appreciate the help!