Complaints, causes and corrections for two different Ford transmissions experiencing harsh downshifts.
The complaint The complaints are harsh engagements and shifts. The scan tool data reveals that there is no amperage command to the EPC solenoid therefor the line pressure is at maximum. There are no transmission codes stored, there are lean codes stored in the ECM. The ABS or the VSC (vehicle stability control) lights may
Complaint: A 2006 Ford Focus with the 4F27E Transmission has complaints of harsh garage shifts as well as harsh lift throttle coast downshifts. All upshifts are perfect and no trouble codes are stored. An exchange valve body complete with solenoids did not eliminate the complaints. The Mass Airflow Sensor was cleaned and checked and the
Mike Riley is once again on the road, this time looking at a Ford truck with a harsh downshift.
Our technical help line is now experiencing a different transmission that can have a variety of severe shifts complaints. It is with Ford’s 6R60/80 transmission. We received one such call from Mr. Transmission in Louisville, Ky., with a 2007 Explorer Sport 4.6L that had 65,000 miles. It shifted fine until you went for passing gear out of 4th. The shift was so brutal that it felt like the transmission went into reverse. There were no codes present. An entirely different call was a complaint of firm shifts and during full throttle kickdowns the vehicle speed signal would drop to zero. It too did not have codes. Yet another call received, all the shifts were extremely severe and it had a variety of CAN BUS codes stored.
A customer with a 2010 Ford Fusion was experiencing erratic harsh upshifts into 5th and sometimes 6th gear. The vehicle was equipped with a 3.0L engine, 6F35 transmission and had 58,000 miles on it. There were no trouble codes; however, the problem was getting progressively worse. The other gear ranges seemed okay and the fluid was in fairly good condition.
Another problem area also can be the throttle-pedal cable. This cable is so long that it eventually stretches (see Figure 1). When you step on the throttle, the TPS responds by lowering the voltage (yes, lower voltage; the TPS ranges from 4.5 to 0.5 volts), at which time the injector-pump lever has not been moved.
This problem came to me from a shop that was working on a 1997 Nissan Maxima with an RE4FO4A transmission that came in with a complaint of late and harsh shifts.