Ford 5R110 sees its 15 minutes of fame
The Ford 5R110, which is used in the newest Ford medium- duty and light-duty trucks, is becoming more popular among rebuilders. A common problem occurs when the 5R110 is replaced with the 4R100 converter. These converters are not designed to be interchanged.
The 5R110 pilot-to-pad height is different than that of the 4R100, which results in improper installation height. As seen in the photo, all internal parts can be interchanged, except for the front cover and the pump impeller. The front cover on the original 5R110 includes the number “6MM” stamped on the pilot side.
Many transmission shops report that they have interchanged these two converters without complications; however, the 5R110 pump impeller has a more agg r e s s i v e fin angle, resulting in a lower stall speed. Using mism a t c h e d impellers may not bring back the average customer to complain, but for a driver familiar with his vehicle’s performance, a complaint may follow.
Members continue to inquire about rebuilding techniques for this converter. Complaints are usually related to the driveability. Constant shift searching is familiar after rebuilding the 5R110. The valve body and solenoid assemblies contribute to the blame. Remember, this transmission requires Ford Mercon SP fluid and it is recommended to use only this type of fluid. Do not substitute.
Found in issue December 2005