If it's a very very faint whine around 70mph it's perfectly normal but I mean very faint, you have to really listen for it, radio/music off etc, I asked about this when I first got my car brand new 8 years ago, after upgrading exhaust, cat, intake, I can no longer hear it, saying that after upgrading Turbo I no longer hear the intake lol.Just got my ST yesterday. Runs great but I noticed it makes a high pitched whine sound when cruising at around 70mph in gear 5/6. Don't really notice it at other times.
It is definitely audible but its not terribly loud and if I drop the speed a bit lower to around 65mph then it seems to get a lot quieter. Also when I decelerate in general it goes away.
I've seen people posting a similar situation with their cars. So is this just normal, or a sign that's somethings wrong? Maybe in the transmission?
The faint whine I'm referring to you have to a bit OCD to hear it.
On these cars they're known to sometimes come out of the factory with not a great deal of Gearbox oil, if you like tinkering it's a 15 min job to drop and replace the gearbox oil, I do mine every 20k miles or so:
Darran's SB MK7ST