My noisy Corolla

I have a 1997 Toyota Corolla. Whenever I get up to about 72 MPH, what I assume is the engine makes an incredibly loud headache-inducing humming noise. The noise lessens considerably above about 80, but I don’t generally like driving that fast! The ‘sweet spot’ of noise occurs between about 72 and 78 MPH, which coincidentally, is the range I drive on the highway fairly often. I took it to a mechanic once who drove it around, and said well this model of Corolla is very noisy and left it at that. I don’t know when the noise first started, or whether it has always been with the car. It seems to have become more noticeable in recent years, but I could be wrong. I am being driven crazy by this noise, and wonder if anyone knows what the problem could be. Thanks to anyone who can help!

If your car is a 3 speed automatic, I’m afraid you are stuck with the noise. My sister traded hers for a Camry because it was too noisy on a trip. The ones with overdrive are quieter, although Corollas aren’t Buicks when it comes to noise levels.

Try to find out where noise is coming from after you check trans,engine oil and tires and pressure.
Crack a back window about 2 inches to make sure it is not air noise.
Try turning wheel back and forth a little while noise is present.
On a back road or deserted interstate use the next lowest gear and try to use same engine rpm.
This will narrow down where it is coming.

Just off hand I would guess it is the timing chain. Can you make it do the same noise when racing the engine in neutral?