Here are the real reasons Brad Keselowski is shutting down his truck team

Brad Keselowski stunned the racing world Thursday when he announced he was shutting down his truck team operations at the end of this NASCAR Camping World Truck Series season.

Kes hinted at financial considerations when he said, on his personal blog:

My contract with Team Penske and the process related to it were definitely a consideration. It is tougher to get deals done now, and it's only going to get harder. I'm no longer a driver who's just starting out, and as I get older, it's more difficult to justify losing money, especially as I look toward the future.

Now, we know how much those financial considerations came into play, as NBC Sports and ESPN have dug deeper into his finances.

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NBC says that the IRS has filed three liens in about a year against his team for a total of about $668,000. Moreover, ESPN reports that Kes has said he loses up to $1 million a year to race trucks.

With the sponsorship troubles roiling NASCAR it's easy to see why that kind of financial pressure would mean the end to the team.