Causes of "bad solenoid pack" for transmission

[lgmagone]

The shop looking at my transmission couldn't find any issues, but did agree to replace the solenoid pack based on my description of the problem. Looking up online, it appears delayed reverse engagement, hard shifting, occasional no shifting can be caused by a bad solenoid pack, so this should fix it.

My question is what causes a bad solenoid pack? This was the root cause of my transmission acting up 24,000 miles ago and has gone bad a second time. I've heard of people getting them changed time and time again and need to be sure that it won't be an issue again.

 

[DAT05EXPLODER]

dirty or low tranny fluid

 

[imp]

Commonest problem, as I understand it, with the solenoids, is failure of the guide bushing in which the plunger rides. Rarely, almost never, is more than one solenoid at one time found to have suffered this failure. Thus, the symptoms are pretty concrete; yours' are not. For that reason, I lean away from blaming the solenoids. My own 2004 lost the TCC (Torque Converter Clutch) solenoid, in this way, trouble code called it out, I replaced the pack of them, and it has remained fine since.

imp

 

[lgmagone]

OK, so the transmission is acting up again. They replaced the solenoid pack 5,000 miles ago which caused the problem to go away for a while, but it has returned. I'm assuming replacing the solenoid pack again will likely only temporarily solve the problem?

Symptoms I'm having:
- brake pedal popping while decelerating - 5% of the time I come to stops
- not staying in 2nd/3rd gear - occasional
- failed to downshift once when attempting to pass vehicle

 

[imp]

7 months later? My guess: problem lies beyond the solenoid module. Are there trouble codes to be read? imp

 

[BrooklynBay]

The EPC & TCC solenoids are modulated, and considered high wear parts. The EPC is very sensitive to debris causing it to clog. The older transmissions allowed you to replace individual solenoids, but on these blocks, you have to replace everything.

 

[JoshMcMadMac]

It could be fluid level.

 

[lgmagone]

Are those symptoms listed indicative of solenoid issues?

It's in the transmission shop now, but they're struggling a bit. They took the pan off and are looking for debris (I don't know if they found any, they didn't 7 months ago). I'm trying to do my homework to make sure they check everything that needs to be done; I don't want it to have to do another tranny rebuild in 6 months time.

 

[BrooklynBay]

Are they using new or rebuilt solenoid blocks?

 

[lgmagone]

I have no idea.

One other symptom - when putting the vehicle in reverse, I have to give it gas, and the car doesn't move. Then more gas, and no movement. Then finally more gas, and I back up really really fast and have to hit the brakes. I've nearly run over people.

This isn't delayed engagement - the transmission engages in reverse but something binds up and then it takes quite a bit of power to overcome the binding and then lets loose. Sometimes my tires will squeal and slip on the pavement when it lets loose.

 

[BrooklynBay]

It's not good for the U joints or the internal one way rear sprag. It sounds like there is low hydraulic pressure.

 

[lgmagone]

I just talked to the shop and they want to swap out the valve body. They said the fluid level is correct and the fluid is clean - no debris. They test drove and could not reproduce the problem.

Does this sound like a resonable next step?

 

[BrooklynBay]

They should examine the valve body to see if there is anything stuck inside of it. Swapping it won't tell them what the original cause of these issues is. Have them check the torque of the valve body bolts, and examine the old gaskets.

 

[DickyDanger]

Sorry to bring up an old thread but i have a question. My 2002 mountaineer 4.6 has delayed engagement going into drive and reverse. Ice cold is shifts flawlessly but once it gets up to temp it shifts hard like kind of bangs into third and fourth and i could be crazy but sometimes feel like the truck is in court gear when im only doing like 35-40 mph and doesnt seem to try and down shift on uphill accents with out me taking my foot off the gas for a split second and then returning to the rpm that i was just currently at. That is the best way i can describe my symptoms. I flushed the transmission fluid and it didnt change and i am 100% positive the fluid is full. Does it sound like i need a solenoid pack?

 

[BrooklynBay]

Did you adjust the bands?

 

[DickyDanger]

No i have not taken the pan off. I have owned the vehicle since august it has 135,000 miles and has done it every day since ive owned it. It was just funny reading the symptoms of delayed reverse engagement and hard shifting pointing towards the pack. And the fact that its fine first thing in the morning but once the vehicle gets up to operating temperature it starts shifting hard.

 

[JonLeeFuller]

No i have not taken the pan off. I have owned the vehicle since august it has 135,000 miles and has done it every day since ive owned it. It was just funny reading the symptoms of delayed reverse engagement and hard shifting pointing towards the pack. And the fact that its fine first thing in the morning but once the vehicle gets up to operating temperature it starts shifting hard.

Did you ever figure out your issues? I have a 2007 hard shifting I drove it to work the wrench light came on. Wasn't on during the drive home I decided to check the codes and it had a high trans temp code. Went to pull it in my driveway and it wouldnt go into any gear after giving it gas could be coincidental but it decided to go into gear. This was my grandmother inlaws and she had the trans rebuilt by ammco about 3ish years ago