I have a 2001 Navigator 5.4L 4x4 that's throwing a P1744 code (Torque Converter Clutch System Stuck in Off Position) along with a flashing OD indicator on the shifter and the torque converter won't go into lock-up.

First off - do I have a 4R100 transmission in this truck?

Second - What can I do to isolate the problem without paying for a $2500 transmission rebuild? Based on some decent google-fu, I have a couple of ideas that I would like to put up for consideration:

1) Replace the TCC Solenoid.
- Can I replace just the solenoid, or do I have to replace the entire Solenoid Pack?
- How can I test the solenoid to see if it needs to be replaced?
- If I do this, then I would also replace the filter and flush the tranny.

2) Replace the Torque Converter.
- If the TCC solenoid doesn't correct the problem, is this the next option?
- I've never dropped a transmission, so not sure if I want to tackle this one.

3) Full transmission rebuild along with new Torque Converter, valve body, etc. Would like to avoid this costly repair if possible.


Thanks in advance for any input!

 

all navigator 98-2002 all have 4r100 transmission, sorry but that all i know
did you tow much though?

 

Thanks for the response. I did tow a fairly heavy 24-foot boat with it several times last summer.

 

Not all Navigators have the 4r100 count the number of bolts on the pan if there are 20 it is the 4r100 if there are 14 it is the 4r70w

 

Thanks! 20 bolts, it is.

 

Best to replace the solenoid pack and the wire harness in the trans. You can do it without removing the trans.
You can buy the solenoid pack and wire harness from most trans parts suppliers.
Sending a PM.

 

Thanks a lot Moto Mel. I appreciate the assist. Can I replace just the TCC Solenoid, or do I have to replace the whole solenoid pack?

 

It is usually best to replace all at the same time, that way you may not have to back in there.

 

Fair enough. I'll have to do some more reading on the wiring harness issue. I remember reading a couple of things about it, but I need clarity regarding which harness, how to replace it, etc.