"It is unlikely that GMAC's ratings could rise to the investment grade level until GM's profile stabilizes or improves, " Moody's said.

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By reaching investment grade, both GM and Ford are considered less risky investments and therefore will be able to borrow money at lower interest rates.

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That way, its access to the financial markets won't be affected should the ratings of GM and GMAC fall below investment grade later this year, as expected.

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