1996 Chevrolet Blazer transmission problems

I work at night driving and often have to break fast for deer crossing the highways. The first time I had to break quickly for 2 deer the vehicle gave a growling sound and just continued at the same speed until I had hit the deer. The last time this happened was today and luckily I was able to swerve around the deer without losing control. I complained of the transmission in march , 2000 and was told there is nothing wrong with it.

The transmission failed with no warning. According to TSB 00-07-30-022 the 4l60e a/t will lose reverse, 2nd, and 4th gears. This is caused by a defective part in the transmission called the reaction sun shell, which was returned to me by the transmission rebuilder. The failure was not maintenance related in any way. The failure of the part was due to inadequate strength. There are numerous aftermarket reaction sun shells that are much stronger and durable than the defective GM part.