When updating a popular, iconic vehicle, stylists always walk a fine line between messing too much with a proven formula or coming across as too complacent and conservative. Perhaps not as emotionally charged as such models as the Ford Mustang or Chevrolet Corvette, the styling update on the 2015 GMC Yukon is nonetheless a significant update, and in some ways, a significant departure from its smooth-sided (as much as a full-size SUV can be) predecessor.

At first glance, the new Yukon and Yukon XL have a much more chisled, angular appearance than their GMT-900 forebears'. Ironically, the new models are aerodynamically sleeker than their predecessors, but you'd never guess that by outward appearances.

Although size and proportions immediately signify which model it is in the GMC lineup, the new Yukon ironically takes some cues from its smaller crossover stablemate, the Terrain. The angularity of the side glass and door panels shows a considerable deal of Terrain influence. However, the jumbo SUVs depart from their junior stablemate with smoother fenders and wheel flares, compared with the Terrain's deliberately boxy and obtuse wheel arches.

Another major departure from their predecessors is the door design, with the upper edge sealing below the roof, compared with the 2014 model's wrap-over door design. The change was reportedly made for NVH improvement and improved sealing.

On the inside, we're much less ambivalent about the changes, with the cabin being a major improvement over last year's uninspired cabin layout shared almost verbatim with most of the Sierra models. The new SUVs have an entirely distinct dash and cabin from the pickups, with stitched details, and a wraparound center console, although as is tradition for GM's full-size SUVs, retain a column shifter. An added upscale detail on Denali models is stitch detailing on the dash panels. The 2015 models also feature push-button start, a feature not offered at any price on 2014 models.

What do you think of the styling changes on the 2015 GMC Yukon and Yukon Denali? A step in the right direction or trying too hard to be different?