5R55E rough shifting

[nesbit]

Hi

I have a 2003 4WD ranger xlt with the 4.0 sohc engine. Only 58k miles. Was fine during the winter. Then just as it started warming up a few degrees it started up shifting really rough/jerky. It was inconsistent but I don’t think it did it in every gear. Now as the weather warmed up the problem is barely noticeable. Fluid is translucent pink and full with engine running. Doesn’t slip. I don’t believe it is flaring just rough. Dealer rightly so says they can’t diagnose if it’s not doing it. But I need reliability at the point of replacing parts proactively. I’ve watched videos on the valve body solenoids, gaskets, etc. Seem like good places to start. But experience and ideas are welcomed.

 

[Transman304]

There are many other components that will affect shift strategies other than transmission itself. Many engine sensors will play a huge part in transmission function. Also ABS problems can give drivability issues. Look into proper diagnosis before going straight for transmission.
Brad

 

[8thTon]

At a minimum clean the MAFS - the computer uses that airflow info, along with rpm and throttle position to determine load and shift points. Next look at the TPS, as it may shift abruptly if it thinks it's at WOT.

 

[nesbit]

There are many other components that will affect shift strategies other than transmission itself. Many engine sensors will play a huge part in transmission function. Also ABS problems can give drivability issues. Look into proper diagnosis before going straight for transmission.
Brad

Good point. I hadn’t considered it could be outside the transmission.

 

[nesbit]

At a minimum clean the MAFS - the computer uses that airflow info, along with rpm and throttle position to determine load and shift points. Next look at the TPS, as it may shift abruptly if it thinks it's at WOT.

could these effect the transmission while the engine still runs great?

 

[8thTon]

could these effect the transmission while the engine still runs great?

It depends - the effect on the transmission shifting can be more obvious than the engine driveability. They are an awful lot easier to check than the gearbox though!

I have a 2004 3.0, and I thought it worked fine, was just reluctant to kick down. I cleaned the MAFS and noticed no change in driveability, but the shifting changed completely. On an older F250 I've had a bad TPS cause the transmission to hold gears to high rpm and bang abruptly into each gear. It thought the throttle was wide open but the airflow and rpm were not increasing, which looked like a very high load.