Thanks to the help of this forum, some time ago I started collecting reliability data and posting results for the 2006- Hyundai Sonata (it's repair rate has been better than average so far).
I'd like to also include previous generations in the research, but haven't had enough owners sign up to participate.
Participants simply report repairs the month after they occur on a one-page survey. When there are no repairs, they simply report an approximate odometer reading four times a year, at the end of each quarter.
To encourage participation, panel members receive full access to the results for free.
For the details, and to sign up to help out:
Vehicle reliability research