along with the debut of the Texas Edition Suburban, the latter due to Texas having the most units of Suburbans sold in the United States (As of August 2014, sales of the Chevrolet SUVs in Texas were up 37 percent) and to celebrate the 60th anniversary of GM's Arlington Assembly plant; production of the Z71 Suburban began in October 2014. As with the previous Z71 Suburbans, this version continued to be offered in a 4WD LT trim only, featuring a front skid plate, off-road tires mounted on 18-inch wheels, a unique grille, running boards, and "Z71" identification inside and out. Fog lamps, front tow hooks, and front parking assist are also included. The 2016 Z71 package was modified again, as portions of the Z71 items added on the Texas Edition package as an optional feature by request from customers was discontinued, making it a stand-alone package. The Z71 package was upgraded to a level trim starting with the twelfth generation models. The Texas Edition Suburban, which became part of the Texas Edition lineup along with the Tahoe and Silverado, was available in both LT and LTZ trims for the 2015 model year, featuring a maximum trailering package, twenty-inch polished aluminum wheels (on LT models), twenty-two-inch premium painted aluminum wheels (on LTZ models), and an exclusive "Texas Edition" badge. For the 2016 model year, Chevrolet discontinued the LTZ package but modified for the LT package without the requested Z71 features. The Twelfth generation Suburban will continue to offer the Texas Edition for the LT and Premier trims only when combined with the Luxury, LT Signature, and Premium packages. LT Signature Edition The Suburban LT Signature Edition, introduced in the 2018 model year, was an optional package trim, similar to the luxury package but with less expensive features, available in the LT level trim only. This option was discontinued after the 2019 model year but will be offered for the 2021 model year. Midnight Edition A Midnight Edition Suburban, an all-black optional package available in 4WD LT and Z71 versions, was introduced for the 2017 model year. This version became part of the Signature Edition Suburban feature for the 2018 model year up until the 2020 model year. Premier Plus On August 13, 2018, Chevrolet introduced a more upgraded version of the top-of-the-line Premier level trim of the Suburban, packaged as the Premier Plus, featuring a 6.2-liter engine, the classic gold bowtie