No one has better vehicle reliability data on fairly new vehicles than the manufacturers, since they keep detailed records of warranty claims. Problem is, they’re not about to publicly release this data.

But publicly traded American corporations do have to report how much they pay out in warranty claims each year at the corporate level. I recently learned that these figures are posted at WarrantyWeek.com.

For GM, we see about $4.5 billion in annual warranty expense, which according to the site represents about 2.5 percent of sales. For Ford, the figure is about $4.0 billion, and 2.6 percent. You’ll also find warranty payments for many automotive suppliers.

Interesting information, but a few obvious shortcomings:

1. We only have figures at the corporate level, not for individual models.

2. Unless sales are steady, and they’ve been in sharp decline for these companies, then the “percent of sales” figure is off, since it’s based on sales in the latest year, while most of the warranty claims will be for vehicles from past years.

3. Some warranty costs are paid by the suppliers–and we don’t know who made the vehicles they’re paying claims on.