easyrider

Ya, I learned the lesson of not getting screwed by car shops. It only took one time. The mechanic also told me he changed the gaskets and I needed a new tranny. It's a done deal with this mechanic, I won't go back to him and I had to bargain him down from 1400 to 950 just to get my car outta there. Anyway, no roof rack, it's a whine or a hum, no vibrato. Just hum in a high pitch and that's the sound my car makes. Same sound every gear. No sound when coasting or pressing gas with clutch engaged.

2001 manual transmission 70k miles. Started making a high piched humming sound between 40-70mph when accelerating, changing gears has no affect on the noise. I think the noise is an A flat but it gets higher piched as I speed up. I drove with the noise for a month but it got louder. A shop said it was the transmission and maybe the rear differential. They took apart the tranny replaced some seals and gaskets and couldn't identify the problem and charged me 1000. It still makes the noise. Any thoughts? I know very little about cars but this problem has inspired me to learn. Thanks for any help!