Following transmission oil/filter change, the harsh 4 -3 downshift returned as usual. However for the second time when the dealer attempted to complete the re-flash on the TCM the TCM fails to commumicate with the test & analyzing tool. WHAT IN THE WORLD IS GOING ON HERE? You drive in the door with everything working fine, except for the harsh shift after routine maintenance and the next thing the dealer is ordering a new EXPENSIVE transmission control module. This problem was created by Crysler and they have failed to fix the problem for years. A software change, providing a time delay reading a line pressure following oil changes would solve this problem. A lot of money has been made due to this well known problem. Its time for a class action law suit!

 

Welcome to DF
These problem do happen. I had a dakota truck TCM that took me four times to flash. After the third time i unplug the abs module,thinking it was causing a problem. I was right, and then was able to perform the rest of the flash.