After multiple months in 2012 of what some might consider irrational exuberance in full-size truck sales, the post-party hangover could be upon us. Compared to last month's double-digit gains for Ford and Ram, the two brands showed anemic growth for September 2012, with the F-Series sales up only 1.2 percent for the month, and Ram up a better, but still tepid, 6 percent.

After several months of triple-digit percentage sales gains, Toyota's year-over-year growth is cooling somewhat, but still shows solid improvement over 2011 numbers, with the Tacoma up 48.9 percent and the Tundra up 39.5 percent. The Chevy Colorado and GMC Canyon, though not huge players in total volume, were also up double digits, while the Nissan Frontier was virtually flat with a 0.5 percent gain for September.

1. Ford F-Series - 55,077, up 1.2 percent
Still the overall volume leader in trucks, the sales pace for the F-Series slowed to a crawl in September. Whether this is indicative of overall consumer demand and weak economic conditions, or simply customers holding out for seasonal rebate and finance deals coming later this fall, remains to be seen. 2013 models are starting to roll into dealerships now, so customers' response to the updates could be reflected in October's numbers.

2. Chevrolet Silverado - 36,425, down 16.6 percent
After showing a slight gain for August, Silverado is back down again, with an even bigger percentage drop than July, although total volume is higher. With GM's highly anticipated 2014 full-size models still nearly a year away, GM is reportedly cranking up production of the 2013s to compensate for the downtime needed to change over tooling for the 2014s, but we wonder if the accelerated production pace is necessary, considering the weak demand.

3. Ram 1500, 2500, 3500 - 25,973, up 6 percent
After a hot August, Ram sales have cooled down quite a bit for September. Overall volume is up slightly over August, but year-over-year September gains dropped off. But on a percentage basis, Ram did the best of the Detroit Three, and with the comprehensively updated 2013 models on the way, Ram could regain the momentum it maintained for the better part of 2012.

4. GMC Sierra - 13,636, down 1.9 percent
The Silverado's near-twin is down for the month, but not nearly as much as its bowtie-clad brother. The silver lining on the sales cloud for September is that the Sierra pulled ahead of the Tacoma for the second month in a row after Toyota's midsizer pulled ahead in July by a scant 245 units.

5. Toyota Tacoma - 12,176, up 48.9 percent
A rarity on this month's list, the Tacoma actually posted a percentage gain over August's sales pace of a 41 percent year-over-year gain. Tacoma's year-to-date numbers are also strong, with overall sales up 30.8 percent compared to the same period last year. Tacoma also outsold its rival Nissan Frontier in September by a nearly 3-to-1 margin.

6. Toyota Tundra - 9338, up 39.5 percent
After breaking through the five-figure mark last month, the Tundra drops back below 10,000 units for September, but still shows a respectable 39.5 percent year-over-year gain for the month. The Tundra comes nowhere close to being a real threat to Detroit's dominance of the segment, but it outsells Nissan's badly dated Titan by a more than 5-to-1 margin.

7. Nissan Frontier - 4354, up 0.5 percent
The Frontier squeaked out a mere 0.5 percent gain for September, down from its 12.8 percent gain in August. Like its big brother Titan, the Frontier is showing its age, but still maintains a following among those looking for a fun-to-drive, no-nonsense truck.

8. Chevrolet Colorado - 2833, up 30.5 percent
Although Colorado sales are a drop in the bucket compared to those of the Silverado, its double-digit gain for September stands in stark contrast to the Silverado's steep decline for the month. An all-new Colorado based on the new global model is expected for 2014, and will likely follow the new Silverado by a few months. With an all-new design and high-tech powertrains expected, the new Colorado could be the most credible threat to Toyota's segment dominance in decades.

9. Nissan Titan - 1792, down 21.9 percent
The Titan continued its lackluster sales performance in September, with its year-over-year decline mirroring its disappointing August performance. As one of the most dated entries in the segment, the fact that the Titan isn't setting the sales charts on fire is no great shock. However, dealers are willing to make attractive deals if you're interested.

10. Honda Ridgeline - 1060, up 51.4 percent
Honda's unorthodox entry into the midsize pickup segment breaks into the four-digit mark for September, representing a 51.4 percent gain over 2011. Honda remains committed to the Ridgeline even as many have asked if it's still a viable product, and larger full-size models deliver similar fuel economy with more capability. Year-to-date sales are up a solid 58 percent.

11. GMC Canyon - 555, up 21.2 percent
After being down 56.3 percent in August, things are looking up for the Canyon in September, with sales up double digits year-to-year. Yet with sales of barely more than half that of the niche Ridgeline, it's surprising that GM has publicly committed to a second-generation Canyon to join the new Colorado.

12. Ford Ranger - 93, down 98.7 percent
The end is near for Ford's compact, at least in the U.S. The sell-off of remaining 2011 models continues, even this close to calendar 2013. We're counting the months until the Ranger drops off the sales reports completely, and with fewer than 100 units sold for September, it seems that milestone is imminent.

13. Ram Dakota - 8, down 99 percent
If you thought the Ranger was on life support, the now-Ram Dakota is even worse off. A mere eight units were moved off the lot in September, probably at substantial discounts. Like Ford's F-Series strategy, Ram believes its fortunes rest in the 1500, 2500, and 3500 models, with Fiat-based small and large commercial vans playing a supporting role. For all intents and purposes, Chrysler's midsizer is gone.