We have a 2010 that sometimes acts similar. My in laws have a really steep driveway. If we hit it at a decent speed the jeep barely makes it up, just as you describe. But if we come to almost a complete stop and let the trans downshift, then it climbs normal with power. It sounds like something with your trans shifting.
BTW, we have a rubicon and are running 35s, stock gearing and no programming, so this may not be the case with your issue but it sure sounds very similar.
BTW, we have a rubicon and are running 35s, stock gearing and no programming, so this may not be the case with your issue but it sure sounds very similar.
