Fitch Upgrades 3 and Affirms 5 Classes of Capital Auto Receivables Asset Trust 2005-SN1

NEW YORK--Aug. 9, 2006--Fitch upgrades three subordinate classes and affirms five classes of Capital Auto Receivables Asset Trust 2005-SN1 lease transaction as follows:

-- Class A-2a asset-backed notes affirmed at 'AAA';

-- Class A-2b asset-backed notes affirmed at 'AAA';

-- Class A-3a asset-backed notes affirmed at 'AAA';

-- Class A-3b asset-backed notes affirmed at 'AAA';

-- Class A-4 asset-backed notes affirmed at 'AAA';

-- Class B-1 asset-backed notes upgraded to 'AA' from 'A';

-- Class B-2 asset-backed notes upgraded to 'AA' from 'A';

-- Class C asset-backed notes upgraded to 'A' from 'BBB'.

The affirmations and newly assigned ratings are a result of increased available credit enhancement resulting from de-levering within the sequential note structure and attainment of target reserve balances. Credit and residual losses have both performed within Fitch's expectations with residual value recoveries posting cumulative gains of approximately $37.9 million through July 2006. As measured by credit and residual value losses, the collateral continues to perform within Fitch's expectations and, under the credit enhancement structure, the securities can now withstand stress scenarios consistent with the new ratings and still make full payments to investors in accordance with the terms of the documents. Notwithstanding the strong residual value recoveries to date, Fitch remains cautious with future residual value performance based on qualitative factors surrounding General Motors Co. (GM) and the auto industry as a whole. These issues include the potential future deterioration in GM's credit profile, continued and prolonged use of incentives, and wholesale price volatility within certain vehicle segments such as SUVs given currently high fuel prices.

As before, the ratings reflect the quality of General Motors Acceptance Corporation's (GMAC) retail auto loan originations, its servicing capabilities, and the sound financial and legal structure of the transaction.

Fitch's rating definitions and the terms of use of such ratings are available on the agency's public site, www.fitchratings.com. Published ratings, criteria and methodologies are available from this site, at all times. Fitch's code of conduct, confidentiality, conflicts of interest, affiliate firewall, compliance and other relevant policies and procedures are also available from the 'Code of Conduct' section of this site.