Ford Motor Co. announced today it has reduced global warranty costs by $1.2 billion during the past two years — $100 million in 2008 and $1.1 billion in 2007.

If there’s a surprise here, it’s that the savings in 2008 were so much smaller than those one in 2007. Even though the big gains in reliability were made in the 2005 and especially the 2006 model years as better engineered new products were introduced, warranties last for three years.

Sales are down, so my initial thought was that much of the savings followed from having fewer warranties to honor. But Ford also said that the per-vehicle warranty repair rate has dropped by 50 percent for U.S. Ford, Lincoln and Mercury vehicles since 2004.

To view Ford’s performance in TrueDelta’s Car Reliability Survey, go here:

TrueDelta Car Reliability Survey results

Of course, the factory warranty is only three years on Fords, and four on Lincolns. How will these new models hold up after the warranty expires, as has recently been the case for the 2005s? With prompt quarterly updates, TrueDelta will closely track these cars as they age.