Nissan's Titan replacement will reach market about four years later than originally planned.

Better late than never? Nissan is certainly hoping so – as are those who’ve long been hoping for an update to the maker’s slow-selling full-size pickup.

It’s been a long 11 years since the original Titan made its debut – and four years since the Japanese maker originally planned to offer a replacement. But plans for the update fell apart, forcing Nissan to return to the drawing board.

What it’s come up with will make a debut at the Detroit Auto Show in January, and several inside sources have confirmed to TheDetroitBureau.com that the plans call for that preview to put the spotlight on a new diesel developed specifically for the 2016 Nissan Titan.

Japanese automakers have long envied their Detroit rivals when it comes to full-size pickups, the one segment of the U.S. market they have yet to crack.

Toyota has tried repeatedly, starting with the original T100 it marketed between 1993 and 1998. It was really more a “tweener,” about seven-eighths the size of American rivals like the Ford F-Series, and fell flat. An updated model, rechristened the Tundra, followed in 2000, but didn’t fare much better. Toyota came up with a full redesign in 2007, and was so optimistic it built a new pickup plant in Texas, but sales still fell far short of expectations – as they did with the update launched for the 2014 model-year.

Nissan was equally ambitious with the launch of the 2004 Titan, offering such innovations as a “Wide-Open Door” system that yawned a full 168 degrees, and the industry’s first factory-installed spray-in bedliner. Nonetheless, Nissan’s Titan didn’t do much better than Toyota’s Tundra.

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Expectations were that Nissan would come up with some quick fixes, or move to an all-new design. It’s initial strategy proved a surprise, the maker announcing it would partner with the struggling Chrysler Group to come up with a version of the Detroit maker’s Ram 1500.

The project was well underway when Chrysler plunged into bankruptcy in 2009, emerging in a new alliance with Italy’s Fiat SpA. New CEO Sergio Marchionne quickly pulled the plug on the Nissan deal, sending the Japanese maker back to the drawing board.

Now, four years late, Nissan is getting ready to bring an all-new Titan to light. Insiders tell TheDetroitBureau.com the goal is to come up with a broader array of body styles and powertrain options – a critical advantage that Detroit makers have had over their Asian truck rivals.

To underscore that development, Nissan will focus on its new diesel during the Detroit debut of the new Titan, and the oil-burner will be available at launch. That could help the new truck pose a bigger challenge to the new Ford F-150 that goes on sale late this year. Ford is promising a significant improvement in mileage thanks to its shift to a lightweight, “aluminum-intensive” body.  How much will the diesel improve Titan’s mileage remains to be seen, but one source suggests the full-size truck could deliver nearly the fuel economy of Nissan’s smaller Frontier pickup.

Currently, only Chrysler is offering a diesel option for a light-duty version of the Ram 1500. GM will launch a diesel for its new midsize trucks in 2016, and may add one for its big Chevrolet Silverado and GMC Sierra lines. Ford has opted to stick with its gas-powered turbo EcoBoost engines for mileage-minded buyers.

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Nissan could certainly use the new truck. It’s currently selling barely 1,000 Titan’s a month, compared to about 10,000 Toyota Tundras – and almost 60,000 Ford F-Series trucks.

The good news for automakers domestic and Asian is that pickup sales have risen sharply over the last 18 months or so as the American economy has rebounded from its worst recession in decades. The question is whether truck sales will continue to be on the rise by the time the new 2016 Nissan Titan rolls into showrooms next year.

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