Hey everyone, newb here with a 2012 q7 v6t.

​​​​​​Long road trip today in high heat. Fan started squeely more than usual. Consistent high pitch.
Then noticed water on passenger side matt. Slow drip from drain hose. Then a new noise. Growl at 100km + under armrest. Even with all fans and ac off. Noise goes away under 95km/hr. Can't pinpoint location.

Thoughts here?

 

You've included very little actual data from/about your car to base anything on.

The water on passenger side mat is most likely a backed up HVAC condenser drain is plugged up; classic symptoms...it just got really full as you were using it nonstop on a long trip; threads on here discuss the importance of keeping drains in windshield plenum and the HVAC, and the sunroofs, clear and functional, and how to maintain them/unplug them, etc.

The fan noise you mentioned is likely from the ventilation fan for HVAC system, yes? Those go out eventually, but are fairly simple to replace. While you are at it, check and replace your cabin filter to be sure it's also not plugged up with debris, which stresses your fan and makes it work much harder than it should be...very easy to do, and also cheap if you do it yourself.

The growling below arm-wrest description over 100km/hour or 65mph, would seem to indicate you need to have your tires/suspension/undercar inspected; it could be as easy as a tire pressure or out-of-balance related issue, but could be more nefarious. Does the noise get better or worse when you go faster? Tires make a 'roaring' noise when underinflated, for example, or if you have alignment issues and abnormal tire wear, then they can make a lot of undesirable noise at faster speeds. You could also have a wheel with loose lugnuts, etc...lots of possibilities, most with simple solutions.

You can search within the forum, but generally the easiest way to find look stuff up is to use a Google search, as it can pull related info from just about anywhere.

Do be a sport though and go to new member section to get a brief walk-through of how to get the most out of this forum, as members require some amount of relevant data on your car to be able to comment with any hope of accuracy...most will skip over if you don't provide the data necessary.