Got the pretty check engine light to come on today in my 2000 LHS. After the key dance and getting P0700 and P1684 for codes I had my friend hook up his Snap On scanner to read the TCM and got code P0740. During a road test, the torque converter locked at @55 MPH and all gears were available. Fluid is good ~2 years old and is ATF+4 and level ok. Speedo works. So I'm ruling out the speed sensors and solenoid. Trans was not in limp mode. Googling P0740 and reading DodgeIntrepid.net didn't yield much but one really good post alluded to (1)Faulty torque converter clutch solenoid valve (2) Torque converter clutch solenoid valve harness or connectors (3) Torque converter clutch solenoid valve circuit is open or shorted. One possible cause is debris in the valve body and that a flush and refill (with ATF+4) might work or that the debris will work itself out if that's the case. I'm thinking the car is telling me to start saving and that a failure is in the cards. The trans has 124K so I realize that.

Can anyone offer some additional info? Is it early enough I buy time with this? The flush is probably the cheapest trick, but if the bands and clutches are going, will I be wasting $$? Anyone install a Mopar Reman lately? Any good? Thank you in advance.