I sued Mercedes Benz of Encino California (Auto Stiegler) in the early '70s... I bought a well-used 1958 220S from a Mercedes dealer and it died just over its 30-day warranty. Total transmission failure.
I talked to the owner of the dealership, and he essentially told me and my wife to pound sand.I wrote letters to the Chamber of Commerce, the Better Business Bureau, and on a whim, to Mercedes-Benz of North America. The CofC and BBB letters were a waste of time, but after I filed suit in the Municipal court - using my long-haired little brother to serve papers - I was called by the owner to come into his dealership and talk.
He and his wife were friendlier than the last time and there was a man standing in the corner watching. He offered me any used American car from his lot plus a return of the 220S and a full refund if I dropped the suit. I found a Plymouth station wagon that friends of mine used to own and accepted his offer.
The man in the corner was the rep from Mercedes-Benz who had flown in from New Jersey to observe!
Good on you too!! The squeaky wheel does get the grease most times. The point is not to back down and go away. You have to be persistent if ignored. The last thing these companies want is bad reviews. Back in the old days, you rarely heard of vehicle re-calls. That crap started when they computerized everything. The problem for a long time has been that these companies offer quantity, not quality, and then they wonder why consumer confidence is down.