Skip the auto shop - Our mechanics make house calls

Q: Tranny erratic shift if the problem is in the tcm would it throw a faulty tcm code ?or not all the times this happens.

asked by on

2007 dakota v6 tranny 42rle erratically shifting replaced hidraulic fluid ,new filter ,mechanic replaced pressure shifting selenoid ,problem did not go away ,then replaced pack selenoid problem continues erratic shifting most of the times tranny locks in limp mode besides all of mentioned truck runs fine ,no hesitation engine runs smooth mechanic said 2 codes come up when hook up scanner p0760 , indicating a fault on the shift selenoid "c"the other code is p0870 hydraulic pressure line malfunction he has said to me that he is not to expert on the electric tranny areas but he estimates the problem is bad ground circuit or the tcm itself on the most part . please tell me your opinion ,truck has 120000 miles ,and ive aready spent 579.00 dlls.on this guy and i can not afford to throw more money away.please help thanks.

My car has 120000 miles.
My car has an automatic transmission.

A: Hello and thank you for contacting Your Mec...

Hello and thank you for contacting Your Mechanic. The code P0760 means that the shift solenoid "C" is operating irregularity. The code P0870 means that the transmission fluid pressure is not determined at its specified pressure.

Check the harness to the transmission and make sure that everything is plugged in. Check the main harness for corrosion and any debris on the contacts. If the harness checks out to be okay, then the problem lies within the transmission. The shift solenoid "C" is probably getting too hot and shutting down. The pump pressure solenoid is not functioning correctly and is maxing out the oil pressure causing harsh shifting.

I recommend replacing the shift solenoid "C" and the pump pressure solenoid. If the problem continues to persist, then the transmission oil temperature sensor could be failing. This symptom results in low fluid, failed pump, slipping transmission, or the computer has lost its memory and needs flashed or replaced. However, I suggest replacing the shift solenoid "C" and the pump pressure solenoid first before doing anything else.

To avoid anymore unnecessary repairs, consider having one of our mobile technicians help you properly diagnose your transmission erratic shift issue.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Truck dies over night. Sometimes within a few hours.

There is an electrical short somewhere. The fastest way is to have a specialist diagnose the vehicle and trace the issue. Short of that, start removing one fuse at a time to check. Reinstall each fuse when you come back...

Q: No working gas pedal, hard to shift

Getting a transmission repair is possible depending on the damage that has been done. The repair could involve simply replacing a sticking transmission linkage and adding transmission fluid to correct a low fluid level. If neither one of those are...

Q: Multiple trouble codes, no spark, no start.

You are getting codes to each and every major sensor on the engine that is needed to run your motor. You either have a major malfunction with the ECU or a problem with the harness not being wired correctly. You...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
How to Renew Your Car Registration in Oklahoma(DELETED)
Having your car registered with the Oklahoma Tax Commission is an important part of driving legally in this state. You will need to do this within 30 days of moving to Oklahoma...