Auto transmission jerks when shifting
at 20mph. Shifts OK at higher speeds.
New fluid and filter.
History of prior trans fluid/filter changes?
Unfortunately, many people do not change their trans fluid and filter every 30k miles, and only think about this procedure late in the game when they begin to experience trans problems. Is it possible that you fall into this category?
Please provide the missing details noted above.
Have the computer scanned for trouble codes before doing anything else. Its best to take it to a transmission shop because you need a high end scanner to scan this transmission and read the transmission parameters. CVI values etc…