Hi all... got a 2015 GC. I’ve noticed in the last few weeks my remote start doesn’t always work(beeps but won’t start) and my phone book doesn’t always load. Today I went to remote start, beeped, but wouldn’t start. Went I got in and hit start button, very “sluggish” but did start, no phone book loaded. It was 11* in Pittsburgh overnight. I do believe it’s the original battery. Only has 35000 miles on it and it’s the 6 cyl. If battery needs replaced, what brand did you use and were there issues after? Heard some horror stories. New to site so thanks to all for feedback.