Sales of the 2014 Chevy Silverado were up 10% last month, despite incentives that trailed Ford's by a wide margin. Photo credit: General Motors Co.

Most automakers' October sales fell short of Wall Street's expectations, as the government shutdown made consumers hesitant to buy. The big exception was General Motors (NYSE:GM), which saw its U.S. sales rise almost 16% on the month -- twice the gain expected by analysts.

GM had a lot going for it last month, but one big thing was its all-new pickups. Sales of the new 2014 Chevy Silverado and its GMC Sierra sibling were up, after posting a big drop in September while Ford's (NYSE:F) F-150 sales boomed. 

What changed for GM? As Motley Fool contributor John Rosevear explains in this video, GM changed the prices on its all-new pickups, and that helped -- but not in the way you'd expect.

Fool contributor John Rosevear owns shares of Ford and General Motors. You can connect with him on Twitter at @jrosevearThe Motley Fool recommends Ford and General Motors. The Motley Fool owns shares of Ford. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.