NEW YORK — While delinquencies on prime auto asset-back securities remained stable in September, subprime auto ABS delinquencies were a completely different story.

Fitch Ratings announced today that that subprime delinquencies have reached an 11-year high, possibly paving the way for a notably weaker fourth quarter,

Prime auto ABS 60-plus day delinquencies came in at 0.71 percent in September, the third consecutive month the index was at this level with no deterioration.

Delinquencies of 60 days or more on subprime auto loan ABS rose to an 11-year high of 4.28 percent in September, an indication of potentially further weakness to come in the fourth quarter of this year, officials pointed out.

Despite the stable performance posted by prime auto ABS in September, the current climate remains "pressured and volatile," according to Fitch. Consumer fundamentals remain stressed given household debt levels and declining home values, as well as the deteriorating job market, executives said.

Furthermore, the U.S. economy is contracting while the stock market is adjusting itself lower posting large declines in September and October. Therefore, Fitch said it expects that the current state of the U.S. economy should translate into increased pressure on the performance of auto ABS during the fourth quarter, and ultimately result in higher loss rates in both the prime and subprime sectors.

The prime 60-plus level of 0.71 percent is 9 percent higher than in 2007, which is relatively stable given the fall months historically produce the weakest performance of the year.

As noted, subprime delinquencies sped up for the month, rising 18 percent from August's level, and came in 40 percent above September 2007.

Continuing on, annualized net losses on prime auto ABS declined 3 percent in September over August, to 1.68 percent, moving off the record high of 1.73 percent set in August.

On an annual basis, ANL were 78 percent above 2007 levels after being 101 percent higher in August. These losses remain elevated and similar to levels exhibited in early 2003, which was the last recessionary scenario, executives highlighted.

Subprime ANL, meanwhile, were at 7.80 percent in September, a 19-percent jump over August and 38 percent higher than a year earlier.

Fitch said it will continue to closely monitor prime and subprime auto ABS performance on an ongoing basis. Fitch's auto ABS indices track approximately $59 billion worth of prime and subprime auto loan ABS. Of this, 68 percent comprises prime collateral while the remaining 32 percent is made up of subprime collateral.