Hi! I'm new to this forum and know very little about cars... but, I have a 2001 Monte Carlo with automatic gear shifting. Has 188,000 miles on it. Other than the transmission, it runs wonderfully.

About a year ago, I began noticing that after running for a while, the car would begin making a whining hum in 3rd & 4th gears, and it wouldn't always shift "right"-- especially shifting into overdrive, it would hesitate at a high RPM before finally shifting completely and the RPM would go down and read normally at about 1500 at 60 MPH. It did it very rarely, and I didn't think very much of it. But last winter when the car was cold, when I would want to go from a complete stop, it would often make a jolt and was clearly hesitant to shift. But again, it didn't do that very often, so I never got it checked out.

Last July, I began noticing the mysterious whining hum was happening again when I first started the car-- not the same as before. Even more scary, I noticed that when I got to above 40 MPH, the car would not go into overdrive. It would try to, but it would hover at a high RPM (about 2400 RPM at 60 MPH) and would stay there and clearly not shift. The whining noise got worse and louder at this point. I have kept an eye on the temperature, and it never goes above anything normal. For a while, besides not shifting into overdrive, things were not getting worse.

This week, things got a lot worse. My mother pulled out onto a highway from a complete stop, and the car clearly did not shift even into 1st gear. It would not go, and when it finally did shift into first gear, it made a violent jolt as it tried to shift into every other gear hence. Still, the temperature remained stable. My mother, after talking to our local mechanic on the phone, checked the transmission fluid, and it was at a normal level and did not have any bubbles that are associated with high temperature.

The car does not have any problems shifting into reverse, drive, neutral, etc. It's only shifting gears that it has problems. Any ideas on what the problem could be? Is the transmission completely shot, making the car useless, or could it be a smaller problem that can be fixed with a new part?

 

SOunds like you have lost your clutch plates inside the tranny. (Meaning they are in crumbs at the bottom of your pan ) Early on it might have been able to salvage the tranmission but now if the clutch plates are gone the gears have become un salvagable. Time for an over-haul or a high performace swap out.