Question

2000 Ford F150 5.4L, am I going to hurt my transmission driving with a P0743 code. I have P0743 and P1740 codes when I scanned my truck

Answer 1

P1740 TCC Malfunction

P0743 TCC solenoid circuit failure

with this code the TCC will never engage, your not going to ruin the transmission you will not have the benefit that a TCC which in the long run save you fuel. the fix you replace the whole solenoid pack

Answer 2

P1740 FORD - Transmission System Conditions
Read more: https://www.autocodes.com/p1740_ford.html

P0743 FORD - Torque Converter Clutch Circuit
Read more: https://www.autocodes.com/p0743_ford.html