I wanted to chime in here. I have 2013 JKUR with 35s (nitto trail grapplers that measure very close to 35s) and 6 speed. I recently re geared from stock 4.10s to 5.13s. I was extremely anxious and nervous about going with such an aggressive gear. But 37s are in my future so I wanted to be ready. I agree with initial post that there is a lot of garbage on the Internet about gears and the chart is over analyzed.

I wanted to say (from my experience only, have not driven 4.88 auto) that I am extremely happy with 5.13s. 1st gear is still useful and I start from it. Sure I have to shift a bit more but the 6 speed obviously lets me choose when. The highway is now enjoyable. I can stay and cruise in 6th gear and accelerate uphill at 70+ miles and all under 3k RPMs. If I couldn't see the needle I would think I was cruising at stock RPMs.

My two ignorant cents. I love my Yukon 5.13s. I don't have SC or TC.