The sales predictions I wrote about last week turned out to be dead-on accurate: On Friday, Ford (NYSE: F) reported that its U.S. sales for September rose by an eye-popping 41% over those in September 2009, right in line with optimistic-looking predictions from industry watchers TrueCar and Edmunds.

To be fair, that number comes with a big caveat: September 2009 was the month after the government's "Cash for Clunkers" incentives program ended. Ford saw a big sales boost during that program, and it's reasonable to conclude that some of those sales were pulled forward and depressed last September's totals.

But even when viewed from less flattering perspectives, it was still a strong month for the Blue Oval Crew -- and one that raises some questions about the company's longtime chief rival.

A closer look at the numbers
Ford's sales, simply put, were strong across the board. The company's PR folks played up the "balanced" nature of September's increases in noting that car, truck, and SUV sales each rose by more than 40% and that sales, excluding the now-sold Volvo brand, climbed by 46%. The high points? The midsize Fusion sedan sold strongly, the just-refreshed Edge SUV had an impressive debut, and sales of the company's bedrock pickup trucks were strong -- though incentives may be a factor there.

And the weaknesses? Sales for the Lincoln brand were strong but less impressive, up 25.6% overall. Ford is poised to address that lag with a just-launched marketing campaign and a promising product pipeline, and I expect Lincoln to be lavished with marketing attention -- not to mention new models -- in the coming months.

Speaking of incentives, although TrueCar estimated that Ford's incentives spending in September would be almost $2,800 per vehicle, up a bit over last year's spending, that's still only slightly above the industry average of about $2,700. And it's well behind TrueCar's predictions for General Motors, Chrysler, and Nissan (OTC BB: NSANY.PK) -- though it's still well ahead of spending by low-incentives stalwarts Toyota (NYSE: TM) and Honda (NYSE: HMC). Traditionally, the Detroit automakers have been well above the industry average on this metric, but reducing incentives spending has been a recent priority for Ford management, and the numbers appear to be moving in the right direction.

Ford's press folks noted that the company's year-to-date sales increase is 21%, more than double the overall industry rate. Yet despite the "recovery," it's still far below recent historical trends. I'll look at that development more closely next week, but here are the takeaways: (1) Ford's fixed costs are now such that it is solidly profitable at current sales levels, (2) Ford's gaining market share, and (3) as the overall level of sales continues to recover, Ford's margins -- and profits -- should continue to be impressive.

Meanwhile, on the other side of town …
I suggested last week that Ford's gain might turn out to be GM's loss. And sure enough, GM's sales were relatively unimpressive on a year-over-year basis: Its 10.5% increase in terms of absolute numbers fell substantially below analysts' expectations. GM likes to spin its sales numbers by playing up per-brand increases and, by the same token, playing down the fact that it had eight brands at this time last year, versus the current four. But if you view the company through that lens, you could argue that GM is making some progress:

  • Chevrolet sales up 19%.
  • Buick sales up a solid 36%, thanks to some strong new products.
  • GMC sales up 42%.
  • Cadillac sales up 11%. GM notes that Cadillac's year-to-date results make it the "fastest-growing luxury auto brand in the industry." Of course, Cadillac was the slam-dunk U.S. leader in the luxury segment until the late 1990s, and it now lags far behind Toyota's Lexus. So GM's note about Cadillac is really less impressive than it sounds.

It's hard to know how heavily to weigh the different breakdowns. GM's overall sales are not increasing as rapidly as analysts would like, but the within-brand results look fairly strong. GM's profit per vehicle has almost certainly risen over last year, with the decreased emphasis on lower-margin fleet sales (about 25% of September's sales were to fleets, down from 30%-plus earlier this year) and the company's continued emphasis on lowering fixed costs.

But this can't be great news for the General as it motors toward its IPO, which is currently expected to happen in late November. News in recent days that GM may be reducing the size of its planned offering might be due to feedback from potential big investors -- or it might be due to GM's own assessment of its near-term market position.

GM is still, for the moment, No. 1 in the United States, but the company's crosstown rival is clearly gaining in a big way.

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Ford's turnaround has been impressive, but is it a buy right now? Tim Beyers thinks another automaker might be a better fit for your portfolio.

Fool contributor John Rosevear owns shares of Ford, which is a Motley Fool Stock Advisor selection. You can try Stock Advisor or any of our Foolish newsletter services free for 30 days, with no obligation.

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