Tranny problems? please help

VW Rabbit 09 - Makes a loud noise coming from back of car, at first i suspected exhaust, but it does not get louder from hitting the gas. The noise gets louder the faster car moves starting around 20 mph. It sounds like it is running at high RPMs but the tachometer does not read over 3000 RPM. There is no check engine light on currently, in the past the light has come on after driving through puddles and then the car could not shift into the higher gears and would be stuck around 40 mph.Eventually it would resolve itself. I have inspected the exhaust but I can not see anything that would cause the noise. The transmission does seem a little sluggish to shift, but it is a smooth shift. Any ideas?

What does the noise sound like?

This is a front wheel drive car, so any sound coming from the rear is something else. Possibly a wheel bearing or a stuck brake. I’d get it looked at ASAP as a bad wheel bearing can cause a major accident at higher speeds.

edit: “sounds like it is running at high RPMs” ? what does this mean?

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