We have had at least one other thread on this over a year ago. Consumer Reports bases its reliability rating on how owners rate various aspects of the car in the annual car survey. If you are a CR subscriber you can see the details of what CR sees as the problem.
These are the items that Z owners (2010 in this case) found below average:
- Engine Cooling (no shock there with our oil overheating issue)
- Minor transmission problems
- Drive system (no idea what that refers to)
- Paint and trim (we all agree about the paint)
- Rattles (uh huh)
- Body hardware
- Power Equipment
- Audio System
Everything else is average or above. Since this rating is based on reader survey responses ( owners of 2010 Z's), it is a bit concerning.I took the survey and didn't find problems in anything but engine cooling, which I fixed with an aftermarket oil cooler. Since all of these complaints (except paint, and cooling I expect) are under warranty,I wonder if this rating speaks more to initial quality than reliability.
It's interesting to note that the 2009 has a much worse than average rating for major transmission problems; the 2010 was above average. Also, the 2009 had much worse than average ratings for brakes and suspension. The 2010's were above average on these. Comparing the 2009 and 2010, there are a few inconsistencies as well where things are reported worse in 2010. Anyway, unhappiness with the nav system was not on the list. We, in this forum, have agreed with most of the listed complaints, so the rating isn't really different from the feedback here.