Media Encoder Render Time 3x As Long as Premiere's

I was exporting a 33 minute 4k Timeline from Premiere Pro and usually when I render I hit "queue" and then media encoder does the render. When I was rendering this clip I noticed that after 10 minutes of the render, media encoder gave an accurate time estimation of 6 hours. That seemed a bit ridiculous so I pulled up task manager to see how many resources media encoder was using, sure enough it was only using 17% of my cpu to do the render. So I decided to cancel the render and render it inside of Premiere Pro instead by hitting "export" instead of "queue" to see if It was going to use any more resources. Sure enough the render used 70-80% cpu the entire time and completed in just under 2 hours.  

Is this supposed to be happening? I was using the same settings for both: H.264 with maximum render quality and render at maximum depth checked. As well as a target bit rate of 25 and maximum of 30Mbps. The file is 4K at 60fps (For YouTube, that's why the low bit rate). I am using the most recent update of the CC 2018 Suite.

I enjoy using media encoder and haven't experienced this issue in the past. Any help would be appreciated!

Windows 10

i7-4790k

32GB Ram

Titan X (Pascal)