Meanwhile, the upcoming 2020 Sierra HDs will be powered by a single engine choice, namely a 6.6-litre turbo-diesel V8 with a maximum towing capacity of 30,000 pounds.
Meanwhile, the upcoming 2020 Sierra HDs will be powered by a single engine choice, namely a 6.6-litre turbo-diesel V8 with a maximum towing capacity of 30,000 pounds.