Zero VGS posted:

Go for it. With regards to texting, yes, you'll need data to text through GV. Though in a pinch, you'll still have unlimited texting with the native number T-Mobile gives you. In practice people tend to reply back to whatever number they're texted from, provided you're identifying yourself. GV will hold a text until it has a split second of data to send it out and receive an acknowledgement back, likewise your T-Mo texts work the same but with more widely available voice signal.

Also what Hotsauce said; there might be an app that can latch you on to any open Wifi point, so using something like that as you're driving with no voice signal could nab a hotspot for the second it takes to send a text.