Actually, I think speaking Spanish would be a secondary requirement. If anyone who can drive a stick behind the wheel of something with more than four tires comes rolling in with pallets of bottled water and cases of Chef Boy-R-Dee and toilet paper stacked up in the bed, the inference is universal: help has arrived. No need to talk about the weather, then.
I think gps should still work fine there. No need to speak Spanish. However when I visited most seemed bilingual.