PO740 code transmission help!

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BigWill

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So I just installed new struts and shocks on my liberty. I added a 2.5"lift to the front and now it's throwing this PO740 code. Any way these could be connected? It has 115,000 miles.
 

LibertyTC

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Not sure what happened there, you could look over electrical connectors at trans.
Code- P0740 Torque Converter Clutch, No RPM Drop @ Lockup.
On level ground after driving a while so trans is hot, take a dipstick reading. Is it on the full line, if not add a bit of ATF+4.
 

BigWill

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Not sure what happened there, you could look over electrical connectors at trans.
Code- P0740 Torque Converter Clutch, No RPM Drop @ Lockup.
On level ground after driving a while so trans is hot, take a dipstick reading. Is it on the full line, if not add a bit of ATF+4.

It was a little below the full line so I added ATF+4. Haven't noticed any rpm drop. Gone through the gears and sounds/feels good. Reset code yesterday and it came back withing 10 miles of driving it. Also has a pending code of the same code.
Before I replaced my struts the only code I had was for the egr valve...planned on replacing it but that code is nowhere now.
 

LibertyTC

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Is the cruise control acting normally? A bad egr can cause rpm related issues.
 

BigWill

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So went for a ride to see if I could tell anything was going wrong and all was good. I got back turned it off and then turned it on again, it shuddered and acted like it was gonna die...like when you run out of gas. Then when I went to start it again it wont start. Still po740 code only.
 

LibertyTC

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What brand model of scanner are you using ? Possibly a shop scanner & read the pending codes & even the trans codes would be a good Idea.
Anyone with a snap on ultra scanner can also read the CVI (clutch volume index) readings...
 

DadOSix

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So went for a ride to see if I could tell anything was going wrong and all was good. I got back turned it off and then turned it on again, it shuddered and acted like it was gonna die...like when you run out of gas. Then when I went to start it again it wont start. Still po740 code only.

Might want to consider fuel pump.

sometimes those electric motors in the pump go bad intermittently.

Do you have a gauge to check fuel pressure? There is a test port on right side of fuel rail.

Can you hear the FP run when you turn the car on, before you hit start? FP runs to prime and pressurize the fuel rail for a few seconds before start.

idk p0740 - no experience there
 

BigWill

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What brand model of scanner are you using ? Possibly a shop scanner & read the pending codes & even the trans codes would be a good Idea.
Anyone with a snap on ultra scanner can also read the CVI (clutch volume index) readings...

Not sure of the brand, I will have to look. Called a friend at dealership and said he thought the fuse box might be bad since we had moved it during strut replacement. Went to start it this morning and it made a horrible grinding sound, shook a bit and died. Now it wont start at all. You can hear it click and try but doesnt. Also new alternator, serpentine belt, and battery.
 

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