Error codes shown in picture below

You do "need" a new transmission. This is a 62TE transmission and they are easily rebuilt.

However, I would suggest starting with checking the fluid. Your gear ratio error codes are saying that the valve body cannot engage the proper gear. This normally results in a rebuild on this transmission. However, your loss of pressure code P0944 is saying that you are most likely going to need a pump as well. If you are putting a pump in it, you should put a valve body as well.

By this point you are almost to the cost of a new transmission which is why people just replace the unit. However, if you are doing the work then it would be cheaper to rebuild it.

I am attaching the info below on this code but when you combine the gear ratio error codes, I would just jump to rebuilding it or replacing it which ever you prefer.

More then likely the compounder unit failed and put metal through the unit and it caused the unit to fail.

No matter what you do, you must replace the cooler or your new unit or rebuilt unit will fail as whatever caused this unit to fail is in the cooler and will release it into the new one. I included this process as well.

Please let us know if you have other questions. Thanks