I had to change mine on recent trip. I had no problem, replaced with pair of channel lock pliers in parking lot.

 

OP says he has already replaced the stepper, so that means he has an 03+ truck. 03+ is in a COMPLETELY different location and uses an oil pressure sensor, not a sending unit. Sending units are 1 wire resistance switches to ground, sensors are typically 2 or 3 wires, and a more precise method of measuring pressure.

 

Actually, I believe the LLY introduced in mid 04 began the present location of the oil pressure sensor- Just sayin

 

You might want to recheck before you post info like this. The change took place in 03 when the GMT-800 trucks received MAJOR revisions to the wiring architecture to reduce the amount of wiring in the vehicles. Part of this change was a switch from a sender to a sensor, and they also relocated the sensor to a location the reads a pressure reading that is more representative of actual oil pressure whereas 01-02 it read oil pressure coming straight out of the oil pump.

 

Trk is a 2003 Silverado 4WD. Sorry I left that out of orig post. Oil pressure sensor is on the drivers side lower engine just in front of the oil level sensor. 4WD front diff and axel block the way. On a 2WD sensor would be easily reached and removed. Still need help in how to remove sensor. Have factory rpr manuals but they don't tell how to remove and replace sensor. Will try to talk to chevy dealer shop mechanic somewhere for help. Thanks for any help anyone can give.

 

Id first try from underneath, since it is just on the other side of the oil cooler. Or try from the wheel well. 22ft/lbs torque on the sensor.

 

Final update on the oil pressure sensor replacement. Tried to get to the sensor from underneath and from the wheel well. Too much stuff in the way. Contacted several local chevy dealers. Part was $124 and labor was 2 1/2 hrs. Must remove oil cooler. Part at local parts store $69. Asked local mechanic to replace for me. Put trk up on rack, was able to get connector off and sensor off w/o removing oil cooler. Total cost $116. Got normal oil pressure. Could not have done it myself w/o rack. Happy now.

 

Directly from GM S.I. - 03 6.6 oil pressure sensor is a 2 wire and 04 up 3 wire .Check out schematics if you have access. I trust my info is correct. Just sayin.

 

Just checked the parts catalog, 03 calls for a GM 98027456. This is the same oil pressure sensor that fits all the way up to 09, and is a 3 wire.