From what I was able to find out, this OTA is to fix an issue with GPS week number rollover that will be happening on Sunday, Nov. 3. Part of how GPS keeps the date/time is by using a 10 bit code to represent the week number (instead of using month, day, and year), meaning that every 1024 weeks (approx. once every 20 years), the week number code rolls back over to 0. That is going to happen this coming Sunday. So the OTA is a fix to properly deal with the week number rollover. If the fix is not applied, then you may have issues using your Navigation system. I also read that this affects more than just GPS/Navigation units, it affects any component that uses GPS for time or timing purposes, such as smart phones. So those of you with smart phones that haven't gotten a software update recently should check for one.
That being said, my wife and I were prompted for this OTA in our trucks earlier this week as well and the OTA failed on both of our trucks with a message, "See Your Dealer". I did check the Uconnect web site last evening and there is now an update available, 18.45.01, that I was able to download and install on my truck and my wife's truck that addresses the GPS issue.
2013 Ram 2500 Laramie QC LB 4x4, Thuren Fabrication track bar, sway bar kit, and 2" leveling kit, Bilstein 5100 shocks, Goodyear Wrangler Trailrunner AT's LT285/70R17, Westin Chrome Ultimate Bull Bar, Weatherguard Saddle Box, Line-X Bed Liner
Attention: TDR Forum Junkies 
