Major Oil Leak....Sending Unit?
 

Ok guys need your help. My 2000 has developed a major oil leak that I cant figure out where its coming from. My sending unit went out sometime ago and I haven't replaced it as of yet. I'm wondering if the bad sending unit is causing the oil leak from somewhere. I have checked the valve covers and they are dry. The leak is coming from above the pan. So it seems to be down to the rear main seal or the the sending unit. If I park and leave it for 15 mins I have a spot about 5 inches in diameter. I can't believe its the rear main simply because of how bad the leak is. She looks like a diesel when idling at a light except the smoke is from under the hood. :( :bigears

You're oil pressure sending unit went out and you haven't replaced it!?! You're braver than I am. I would clean all the oil off your engine and drive it up on some ramps and wait for it to start leaking. Ether works great to clean oil off of just about anything but be warned its Highly Flammable

The sending unit is at the top back of the motor. Check behind the intake manifold and see if you feel oil. Another spot to check is on the driver side by the oil filter. There is the oil temp sensor and an oval gasket. I've seen this give way and cause massive oil leaks before. If not that the rear main or there is also a yellow rear oil plug behind the back engine cover.

Have you checked the oil filter to see if it's tight? I am alarmed sometimes to find how little torque some installers use when installing the oil filter. I always use 3/4 turn after the gasket makes contact. (Sometimes SLIGHTLY more but NEVER more than one turn)

C5s are supposed to have the oil filters torqued on (22 ft lbs), it amounts to 2.5 turns after contact ! Some say it is to prevent leaks, others laugh at it.

Also, you could have the old oil filter gasket stuck to the oil filter bearing surface.

This is most definately not from the oil filter. Doing some research on here, Thank God for the Corvette Forum, it appears that a bad pressure sending unit can cause a major leak. Im going to replace it this week and hopfully that cures the issue.