It takes a special kind of voodoo to turn $46 billion into negative $1 billion, and unfortunately for shareholders in America's biggest carmaker, General Motors (NYSE:GM) possesses just that kind of magic.

Today, the struggling Detroit icon made good on its promise to deliver a huge first-quarter loss. The headlines you see today will vary, some claiming that the real loss was only $839 million. I'm all for tagging GM with the full bill, including one-time hits, which comes to $1.1 billion, or $1.95 per share. "Special items," including charges for layoffs and impairments, are likely to continue as the firm battles back, so investors should get used to them.

The trouble is pretty simple: The car divisions continue to rack up losses that cannot be outweighed by profits on the more profitable lending operations. Using cars as a sort of loss leader for the financing wing is nothing new, but competitor Ford (NYSE:F), for the time being, is having better luck with its banking.

Before tax effects, equity income, and minority interests, the loss came to $2.8 billion on the car side, compared with a profit of only $1.1 billion on the financing side. North American auto operations provide the lion's share of the red ink. Factor in a nearly $1 billion increase in interest expense year over year -- ah, the beauty of debt -- and you have the recipe for today's bad news.

It would be nice to be able to say something like: "Hey, these are just GAAP losses! Let's revel in the cash flow!" But things are even uglier there. The direction of cash flow is decidedly out. The $4.1 billion consumed by operations for the first quarter of 2005 is not only a heck of a lot more than the "official" $1.1 billion loss, but it's also 26% greater than the $3.2 billion cash outflow for the prior year's quarter. What's that? You thought GM earned money in that quarter? Welcome to the difference between earnings and cash flow.

CEO Rick Wagoner was frank. He said the firm needs to do better on cutting costs, and he singled out health-care expenses as a particular challenge. The way I see it, everything is a challenge for GM. I continue to get email from folks who insist that GM is the "bargain of the century." Well, I think I started to hear that noise when GM was still at $35 a stub, only a few weeks back. I don't happen to think GM's in real value territory yet, and to judge by today's 4% haircut, neither does the Street.

Others ask whether GM's current 8% dividend yield isn't just too good to pass up. If that's on your mind, I refer you to the cash flow sheets for the truth about GM's condition. Do the math yourself, and come to your own conclusions about how long that payout will continue. My guess is: not forever.

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Seth Jayson thinks dividend lovers should lay off the GM and take a free peek at Mathew Emmert's Income Investor picks to find companies that can actually afford to keep paying their dividends. At the time of publication, Seth had positions in no company mentioned. View his stock holdings and Fool profile here. Fool rules are here.