904 shifting funny

It's mostly 1-2 when it shifts it's like someone is putting the brakes on when its changing gears. It's a regular valve body. The transmission is from TCI. I have a kickdown cable on it. It was fine then all of a sudden it started with this .

The level looks to be on the low line on the dipstick while checking it in neutral. I do have a auxiliary cooler and a deep pan.