I have an 04 Durango 5.7 4x4 205k on body 160k on engine. I put an engine in it 5 years ago for my brother and bought it off him after he crashed it. Had no problems after i put the engine in. Put new plug and wires on it. Eventually the upstream 02 sensor codes and transmission code code came on. Replaced all 4 o2 sensors with NTK o2 sensors. Being dumb I somehow ordered the sensors for an 06 Durango instead of an 04 off of rock auto. I realized this after i already installed the front 2, fit fine even though different part #s. The realization came when the 2 down stream sensor plugs didn't match up. I spliced the new 02 sensors into the old 02 sensors connectors. After i reset the codes the truck will start and run for 100+ miles with no codes. But, when i start the truck for a 2nd or 3rd time the cel will come on. Both P0141 and P0161 come up. I tried adding spacers, didn't help. Replaced coolant sensor, didn't help. On the scan tool im using the down stream o2 sensors are in operating range, which really confuses me why the codes are showing up. Is using the wrong year o2 sensors my problem? Im guessing i only need to replace the rear o2 sensors, since that's what codes are showing up. Any help would be greatly appreciated.