02 Trany problems

[blockisle9]

I have a 02 Explorer XLT 4X4 with 27k miles; it was built in April of 2001.
I bought it 7 months ago with about 20k miles.
It’s been back to the Dealer about 7 or 8 times for shifting problems sluggish and sometimes bangs into gear.
First couple of times they reprogrammed the trany,
Then they replaced the trany with factory reconditioned one. I still have the same problem and now a new one. Some times when stopped at a stop sign then step on the gas the car is in an upper gear and has now power until it down shifts in to 1st with a loud bang.
Anyway I’ve been back to the dealer a few times but they cannot duplicate the problems, and there are no codes stored in the computer and no TSB's on the problems. They basically told me with out being able to duplicate the problem i'm going to have to live with it. Any ideas?
Thank You
Lenny

 

[Alec]

Hmmm, since you've done almost everything else, have them replace the TPS, throttle position sensor. This sensor going bad can often lead to tranny problems. Good luck!

 

[blockisle9]

Thanks for the reply
Would'nt this store a code?
Thanks

 

[Majisto]

Nope, it won't always throw a code. I think whomever owned it last abused it. It happend with my Taurus. The tranny clunks into gear and the 1-2 shift is hard as heck. Your Explorer transmission should NOT be doing that. The 5R55E is a very smooth transmission. I have had no problems at 80K, so I think something is very wrong...try getting it flushed and re-filled with synthetic fluid. Also unplug the negative battery cable for about 20 minutes so the computer gets erased. Then drive it around and let it re-learn its shift pattern.

 

[blockisle9]

Thanks,
That was all done, including the transmition being replaced with a remanufactured transmition. This was done by Ford
Thanks
Lenny

 

[Jason_25]

Majisto, he has a totally different 5R55W tranny.

Have you tried going to another dealer? I have a pretty good idea that it's not the tranny, it's the computer. Maybe they didn't reflash it correctly?

 

[Majisto]

Originally posted by blockisle9
Thanks,
That was all done, including the transmition being replaced with a remanufactured transmition. This was done by Ford
Thanks
Lenny

Why in the heck is it shuddering then? How bad does it bang into gear? Does it shake the truck a bit? Do you feel it in the gas pedal?

 

[Majisto]

Originally posted by Jason_25
Majisto, he has a totally different 5R55W tranny.

Have you tried going to another dealer? I have a pretty good idea that it's not the tranny, it's the computer. Maybe they didn't reflash it correctly?

They use the wider ration 5-speed now? When did they change over to it, the new body style?

 

[Jason_25]

Yeah all 02+ explorers (V6 and V8) use it.

 

[dogfriend]

I think that Alec is on the right track with his suggestion. Several of the sensors, including the TPS, will have a effect on the shift scheduling and harshness. Since replacing the Trans didn't solve the problem, it seems likely that one of the sensors is bad or (less likely) the PCM is malfunctioning.

If they havent done this since replacing the trans, they should hook up a scan tool and monitor the suspect sensors and the transmission line pressure while driving under the same conditions that cause the problem. If they won't do this, then I would find another dealer to take it to.

I wouldn't accept their suggestion to live with the problem, especially since they thought it was serious enough to replace your transmission.

 

[blockisle9]

Thanks all for your input,
First let me ask whats the PCM? My problem is that I can not duplicate the problem, I could go 3 or 4 weeks with out any of the problems happing. Thats the problem when I drop it of at the Ford dealer they drive it for a few days any every thing checks out while they have it, they have been very helpful but with out experinceing the problem they can not do any thing.
Thanks once more for all your input.
Lenny
PS- This is my third Explorer 94/97/02 even with this pain in the but problem I still would recomend them

 

[dogfriend]

PCM - Powertrain Control Module aka the engine control computer

On the 1st gen Explorers, the PCM uses EEC IV (4) to control the engine emissions, fuel/air mixture and ignition timing. On the later models like my 97, the PCM uses EEC V (5) to control the engine plus the transmission. The 5R55E in my 97 uses Electronic Shift Solenoids to apply the bands to shift gears and a Variable Pressure Solenoid (EPC -Electronic Pressure Control) to control the line pressure (working pressure) in the Transmission. Your transmission is probably similar but even more sophisticated with regard to electronic control.

For example, on the 5R55E, the PCM controls shift points and line pressure by gathering signals from the engine sensors and from sensors built into the transmission. One of the sensors in the transmission is a Trans Fluid Temp sensor (TFT) which is used by the PCM to adjust shift pressure to compensate for hot or cold ATF. Since you have replaced the transmission and still have the problem, it seems likely that one of the engine sensors is not working correctly (or the wiring is faulty) and is giving the wrong info to the PCM.