I apologize in advance for the length of this but it might be useful info to help someone else......

My 2003 with the 48RE auto had developed a shift issue. Between 50 and 70 MPH, the torque convertor clutch (TCC) would engage and disengage every few seconds.....Overdrive would not hold either and would drop back to 3rd. This issue was worse when I was towing my 7000# RV. 1st thru 3rd shifted normally at all times.

Here's what was done........

-Throttle position sensor replaced (TPS)........no change
( I calibrated this sensor as per info from this group several times...didn't fix the problem but I do know what a 'dead' pedal feels like now....weird)
-noise suppressor from DTT installed..........no change
-disconnected alternator entirely and drove....no change (proved electrical -spike not an issue)
-Chysler 5 star dealer tested all sensors rock solid (tested at in-town speed even tho they were told issue exhibits at highway speed only- 3 days)
-spent 3 weeks at reputable tranny shop and got scanned, under load, 3 times..(3 days off work to hook up the trailer and take it out on the highway with the tech and his scanner...)changed output sensor.....no change
-back to Chrysler 5 Star....check connections on PCM and ECM as per TSB...
-check every **** TSB
-Chrylser 5 Star dealer has a tranny tech old enough to remember the push-button automatics in the 60's......I browbeat the dealer into renting him and the scanner for a couple of hours.......he could see (and showed me on the scanner) the engine RPM;s ranging from 0 - 5700 RPM while the tach showed a steady 1200 or whatever I was doing at the time....he figured the crank sensor was an issue......

Once I got to 50 MPH, the tranny governor pressure started to bounce all over the map even tho it was steady below 50 MPH.....strangely, once the governor pressure started to jump around the crankshaft sensor output steadied up. There must be a connection somehow. Once the tranny governor pressure started to bounce around, the shifting went all to heck as well...the TCC locking and unlocking....O/D was only a dream....etc.

The tech changed the crankshaft sensor and the tranny governor and sensor......

Runs like a dream now.

Hope this helps someone.......a lot of expense for a simple solution. I get the feeling that the scanner used by Chrysler is more informative than the one the tranny shop was using.

RobC

 

I didn't realize they put the 48RE in an '03.

 

According to the dealership, apparently on the later models....or the previous owner had it done. Personally I'm happy it's there.