Converter codes showing slippage
Eddie from Transmission Express in Georgia called the newsletter for help on troubleshooting his 5R110 converter. He says he gets converter codes showing slippage after rebuild. He replaced the valve body to no avail. He replaced the torque converter again with a Ford OEM converter as suggested by Ford, and still converter codes occur.
After reviewing his problem and speaking to some of our TCRA experts, it was recommended to change the external filter that is in line with the cooler system; however, this did not solve the problem.
The 5R110 converter and transmission require the use of a special ATF. When we inquired about the type of fluid that Eddie was using, it was determined he was using Mercon IV, as the Ford dealer recommended. This vehicle, which came equipped with a 6.0L engine requires Mercon SP, instead of the IV that was being used. It has been determined that this transmission is very sensitive to the correct ATF. At present Ford is the only recommended supplier of this fluid and should be used without any additional additives.
After flushing the unit thoroughly and replacing the fluid twice, the problem corrected itself. Again, this is another example of using the correct fluid to prevent problems. For more information about the correct fluids to use call Dennis Sneath at Midco Lubricants, 1-800-554-2668.
Found in issue 03, 2004