The answer to the riddle is three words. I had tried some single words and then went on a whole different tangent, before going back and trying the longer three-word version. Also, as a hint, watch the movie Cars.

Ok i got the killer of the mother road…now what?

This one was rough and the first two hints told me what I already knew, the last one still didn't help because I was using the wrong size grid. My research on the route cipher said part of the code was the size of the grid so I was trying all combinations of 6x4, 4x6, or even 6x6 grids with empty space. I tried the 6 shapes eventually on my own but it was useless in the wrong size grid I also got really hung up on the Chicago to LA direction and tried to start the decryption in the northeast corner and end in the southwest. A very frustrating puzzle

You're not decoding a route cipher, you're creating one. -_-

This puzzle really has me stumped: I’ve been working on it for several days now, read all three hints, and I just can’t crack it.

I’ve tried so many arrangements of the route cipher, using the two sixes as it says the third hint, but it’s never anything coherent. The third hint also says that there’s another step and that the riddle is referring to something else. I thought that might be the Route 66 song, but I can’t find any way to work that into the puzzle.

Any further hints from people who’ve figured it out would be greatly appreciated.

The worst puzzle yet.

Haven't started yet - but that sign is on the wrong side of the road ... wonder if that's a clue?

Nope. Finally got this but needed all three clues - IMHO the red dot is well deserved but still a fair puzzle.