This is the totally redesigned 2019 GMC Sierra 1500, caught while out testing in Los Angeles.

Like its fraternal twin, the Chevrolet Silverado, the Sierra will receive a major rework for 2019, including lightweight materials, new powertrain combinations, plus more refinement and technology.

Sharpshooters caught the disguised Sierra running around in LA, but all the camo couldn't hide a few obvious details. GMC's prominent upright snout will feature prominently on Sierra's front end, flanked by new corporate C-shaped LED headlamps, similar to the design on the new GMC Terrain. Moving rearwards, the Sierra will gain a similarly integrated rear bumper dual exhaust setup as the Silverado.

Notably, the Sierra will seemingly stick with GM's "controversial" square wheel wells.

The GMC will also continue on with the tried and true 5.3 and 6.2-liter V8s, but they'll also be joined by a new 3.0-liter inline six turbodiesel slotted for production in Flint, Michigan, making GM's half-ton pair the only with a diesel engine built in America. Transmission choices are likely to mirror the Silverados 6 and 10-speed units.

Look for the Sierra to make an official appearance at either the Chicago Auto Show next month, or the New York auto show this spring. Like the Silverado, it's expected at dealerships in the second half of 2018.