Sqeaking noise when accellerating in lower gears.

I hit a pothole this weekend, and now my 98 Yukon is making a new noise.

It's making a squeaking noise when accellerating in lower gears. Once you get up to 2nd and 3rd gear, the squeaking goes away. It feels transmission related becuase the squeaking occurs when giving it gas, not just when the car is coasting along.

Does anyone know what this might be?

My 98 Yukon has 190k miles on it.

Thanks!