[snizzle]

Hope this is true:

"Base WT (Work Trucks) and LT models will have 237 hp and 259 lb-ft of torque. A Plus version of this same engine with 310 hp and 390 lb-ft of torque will be standard in Z71 and Trail Boss models while available in the WT and LT trims. The enthusiast-oriented off-road ZR2 model returns and has 310 hp and 430 lb-ft of torque from a high-output version of the turbo-4, which will be available as an option on all trims with a confusing caveat: WT and LT buyers will have to option up to the Turbo Plus and then from there the High-Output engine when ordering their trucks."

I guess it's just the tune varying outputs. Global B is going to make it hard on the aftermarket so I guess buy the tune you want up front?