I've done this mod and everything works fine - it's just plug and play.
But here's some information....
A base display audio equipped 2013, which is what I had, does not have a Voice Control button on the RH steering pad. The JBL and Navigation equipped do. I verified the wiring on TIS Techinfo. There are 3 wires. Two control and one ground. The same 3 wires are the only wires used on either Steering Wheel Control system.
I verified that Voice Control works on the 2014 unit - I went through the "voice training" on the Navigation unit. It hears me and calibrates the system. (oh, the answer to an obivious question - there is NO way to engage the Voice Control on this unit with anything but the steering wheel control).
So.... I researched buying the controls WITH the VC button. Pricey. Both LH and RH must be purchased. $280. I'm wondering if there is a market for my controls if I go down this road.
If someone were interested in purchasing my steering wheel controls, I'm pretty sure that trucks that do not come with steering wheel controls only have a 7-way vs 16-way spiral cable assembly. That would mean there would be no way to get the signals out of the steering wheel without also purchasing a spiral cable assembly. Could be wrong. If no swap is required, then more than likely the proper 3 pins are wired, and maybe wired to the radio harness. Wondering if anyone could shed some light on this as I do not know anyone with a real basic truck.
Also, I was thinking of purchasing the 2014 steering wheel controls (when available). They are the same shape so they'll fit, but add some additional buttons. Again by researching the TIS site, I determined that connections are the same for existing buttons. The additional buttons add "left, right, up, down, enter, return" - somewhat more useful on some navi unit screens. These additional buttons use a 3rd control wire. As my spiral cable is already 16-way, I would only need to add this third control wire to the proper pin at the S8 connector and at the N25 connector - not very difficult at all. Actually it may be there already, I'd have to check.
Again only worthwhile if I were to sell my steering wheel controls...
I guess this all sounds pricey, but I purchased the 2014 Navigation unit for $450, sold my display unit for $225. So I have upgraded my radio to the Premium Entune, with Navigation for $225 total so far. New steering controls would make that about $500 total. If I could sell my controls for maybe $150, that would mean the whole thing would have cost me $350, which is FAR less than I would have paid for decent after market system, and an AXESS or similar SWC controller.
The TIS site is very useful. Too bad it is so expensive. They've got me twice for $15 and I downloaded all I could. I guess I need to add $30 to the cost of my upgrade! The wiring diagrams (well the color ones) are not easily downloaded. No way to save them off outside of the SVG viewer. But any PDF that is relevant, I grab. The diagrams and interactive links to connectors, locations make life easier instead of just trying to guess what wire is what.
I had a Subaru Outback and had access to all of this stuff for free, I was kind of surprised when I found I had to pay!