It's been a tough couple of months for shareholders in Navistar (NYSE:NAV), one of the country's biggest truck and engine makers. Back in March, the company had to report that the SEC was formalizing its investigation into the firm's books, specifically the restatement of a few years' operating results.

That was only a couple of days after the firm said it would be filing its first-quarter results a bit late, because of the difficulty of completing the abovementioned restatements. There's also the small matter of a reported parts shortage. ("No problemo," says management.)

Today, the firm released yet another "oops, my bad," in the form of a revision of the 11-day-old first-quarter earnings release. Those who remember those numbers will recall the happy headline that Navistar fed to the press, including the Wall Street favorite, "exceeds guidance."

The previously reported, guidance-whomping $0.27 per share has been knocked back to $0.24 per share. Anyone else wondering why management didn't bother to point out in the headline that this new result didn't even hit the high end of guidance? Silly me, I forgot rule No. 1 of the earnings-release game. When the truth hurts, bury it beneath something that looks better. In this case, the "better" is yet another reassurance that full-year guidance will be met.

You might take the muted reaction in the stock price today as an indication that the Street believes the latest line. Or you might take a peek at the 37% drop the market has inflicted on shares over the past year, much of it during the last month, and figure that quite a few bad expectations have already been priced into this stock.

Whether you think that makes Navistar a value depends on your faith in the future of the sizeable revenue gains that have been the staple of late. That requires a bit of crystal-ball-gazing on the economy itself, since it's economic activity that dictates the direction of the truck maker, along with competitors like Ford (NYSE:F), GM (NYSE:GM), Paccar (NASDAQ:PCAR), and DaimlerChrysler (NYSE:DCX).

With a cyclical heavy-machinery maker like this, unfortunately, timing is already tough enough. It's even more difficult when the underlying numbers remain in flux, and some of the profit isn't of the highest quality -- something I talked about back in December. My suspicion is that the strange numbers game is likely to continue.

A final exhibit that sets my Spidey sense to tingling: A recent 8-K reports a substantial cash award to the guy who's presiding over these messes, CFO Robert C. Lannert. The board gave him an extra $221,000 on top of the $1.4 million he already took home for 2004. The reason? Yet another math error.

For related Foolishness:

  • Navistar looked bad to me back in December.
  • And not so hot last May.
  • The stock has been chopped back from $47, when it looked like all was well.

Seth Jayson yearns for his own school bus, but at the time of publication, he had positions in no firm mentioned. View his stock holdings and Fool profile here. Fool rules are here.