Originally Posted by motoyen  Did BMW ever address the structural integrity of the strut towers problem some owners were having? I remember reading that some owners had noticed that their body panels were not aligned properly and they thought the cause was the aluminum strut towers being too weak. |
This issue turned out to be a non-issue but took an interesting twist. It first came to light at the Z8 Club in Germany and got some emotional discussions going on the internet. That club took the issue to BMW and at the same time began a detailed investigation that took about 10 months to complete. The result of the investigation, which was comprehensive, was that the Z8 was no weaker than any other BMW as far as shock strut towers are concerned. They found that cars that had actually suffered strut tower damage had all been in accidents that would have damaged the towers in any car.
However, all of us Z8 owners became aware through this exercise that any frame repairs to the Z8 would cost a lot more compared to a car with a steel chassis. Domed strut towers in a Z8 cannot be pressed back flat because they are aluminum. A correct repair involves welding new chassis pieces to the front of the car, which means disassembling everything forward of the firewall, doing some tricky Aluminum welding at one of two certified BMW aluminum frame/body shops in North America, and then putting it all back together. Holy cow. The costs of such a thing can be enormous.
The Z8 Club in Germany has tight connections inside BMW AG and somehow BMW was convinced to do something about helping members even though the company was adamant that there is nothing wrong with the car. So BMW came out with a reinforcement kit that they called a "Performance Package". This kit applies reinforcing plates at the top of the shock mounts, and adds a strut brace across the engine compartment. In the meantime, owners theorized that an additional improvement would be to get rid of the very hard run-flat tires that came stock on the car.
Facing the small possibility of a really big repair bill for a minor accident, I decided, as many owners did, to install the Performance Package for peace-of-mind. I also happily dumped those crappy run-flat tires in favor of some really good Michelins.
So, yes, BMW did address the perception that there was a problem, but there never was an actual weakness in the car. And as far as the body panels go, yes, there was a few cars that had doming and frame distortion due to accidents and these had some excessive panel misalignment.
