2003 T Bird Transmission and PCM replaced and still shifting harsh

[jjswan]

My 03 T-bird had transmission rebuilt and still has harsh shifting. Transmission shop said problem was PCM now and not the transmission. Went through 4 different rebuilt PCM (can't find a new one) and still have harsh shifting and now E shows up instead of D5 when shifting. Transmission shop continues to state that this is a common problem and it is the PCM. Two different online PCM computer rebuilders say the PCM's are fine. Any suggestions? Thanks in advance.
Jeff

This page contains affiliate links for which I may be compensated. As an eBay Partner, and Amazon Associate I may be compensated if you make a purchase at no cost to you.

 

[Aquarius]

My 03 T-bird had transmission rebuilt and still has harsh shifting. Transmission shop said problem was PCM now and not the transmission. Went through 4 different rebuilt PCM (can't find a new one) and still have harsh shifting and now E shows up instead of D5 when shifting. Transmission shop continues to state that this is a common problem and it is the PCM. Two different online PCM computer rebuilders say the PCM's are fine. Any suggestions? Thanks in advance.
Jeff

I am experiencing this same issue as we speak. I've had 2 PCM units related and worked for a while. Then at the end of the driving season, the car went into limp mode and I got the "E" designation. Took to the shop and was told the transmission was shot. They put in a remanufactured unit and while they were doing that it was discovered that the throttle cable was loose. That was tightened and was told that was why the car was not starting all the time. I've had the car back for a month and all is well, till yesterday when I went to start. It went back to the issue of not starting again. took 2 tries and I started and has several times since then. I'm going to have them check and see if for some reason the throttle cable is loose again. This is driving me crazy had to enjoy a ride in the car when in the back of my mind you're not sure the car will start again. One trick was to jiggle the shift selector and that usually worked. But that made sense that the cable was loose and by doing that it somehow made contact allowing it to start. I don't know I'm not a mechanic here and this is getting frustrating. Does anyone else have an experience to share??

 

[Liquidlounge]

What fluid was used when the transmission was rebuilt? In my experience, the 5R55 does not respond well to "all trans" type fluids. When I bought my 2003, I thought it shifted like crap and I remembered the previous owner stating the trans fluid was recently changed at an oil change place. I did a partial change on the fluid with Motorcraft Mercon V and noticed an immediate improvement. The next oil change, I did another partial change and there was a further improvement. The only other currently available LICENSED by Ford product that I could find was Castrol, so I went to the dealer and bought the Motorcraft brand at appx $7 per quart. I would not use the Valvoline Merc V as it is not a licensed product, so the makeup of the product will not be the same. The right spec is really important on older transmissions - unlike motor oil.

 

[jjswan]

I'll ask about the transmission fluid. Taking it back in next week to have them look at it but sure they are going to push the PCM is the problem again. One thing that substantially helped the harsh shifting was a PCM reprogramming TSB protocol that involves shifting from park to reverse 5 times, drive to reverse 5 times, reverse to drive 5 times, and then neutral to drive 5 times. Interestingly the transmission shop continues to deny that this protocol is necessary although ford clearly states it is and it has made a noticeable difference. The "E" designation is something new though. Thanks for the input.

 

[doug7740]

As per page 12 of your owner's manual it states; If the transmission PRNDL indicator displays an “E” character or flashing, this indicates a transmission malfunction and may cause damage to your transmission.

Since you have already installed 4 different PCM's and you are still experiencing harsh shifting, the probable cause of your harsh shifting could be high line pressure, transmission fluid level or condition, one of the solenoids in the solenoid body assembly or the the solenoid body itself. Did the shop that rebuilt your transmission check for fault codes in the PCM? Did they perform a PCC pressure check as per Technical Service Bulletin 05-21-8?

doug7740
1955Thunderbird Blue

 

[jjswan]

They did check codes. In fact they replaced Solenoid last week( although they didn't think that was the issue). Codes that are currently being thrown are P0967 Pressure Control Solenoid B Control Circuit High and P0778 Pressure Control Solenoid 'B' Electrical. I did find a thread on this website about E code being a Valve Body Assembly issue. @Doug, I did read that TSB upon your recommendation.