We have no shaker bass speaker or wiring even though the 2017 says shaker on lower center console. Some seem to think since the 2017 has a ninth speaker in top center of dash that is what they mean. But that doesn't work either since you can look down through the windshield at the top center of dash on the 2016 and there appears to be a speaker there also.
There is a wiring chart that shows there is a wire there for a subwoofer. I had a custom box built like JL audio box, or the shaker box, but I did not see a wire back there. I am running off a Alpine and I2 with a bass knob setup for my sub.
There is 9 speaker and 12 speaker system, you have to change your existing amp to premium amp to get low out to work, then you can plug in shaker amp/speaker system and change the rear deck speakers to coaxial from mono's, alot of work for minimal upgrade. Easy way tap the rear speakers high ouput and use to drive a home grown shaker, read the thread lots of ways to updrade