'94 SSE 3800 Bonne

I have a mechanic verify what I thought was a knock coming from the lower engine area.

I guess I'm a bit disappointed being only the 3rd owner and knowing how well the 1st two owners took care of the car. Also because every hypes up this car/engine as the best one GM ever made.

Does anyone have any ideas what is causing this noise?

I bought the car @ 108,000 and didn't notice the knocking until around 125,000.
Everyone I talk too has doom and gloom and tells me that it is probably my main bearings and rings that need replaced, but then they follow it up by saying that if I've let it go this long that then your getting into a more complete engine overhaul (forget that!!!). Not for a $3000 car.

Is there any chance that you can make a video of the engine so we can hear the sound. Try pointing where you think the noise is coming from. Is it while driving or at idle? How does your oil look? Is it at the correct level, is it clean or dark? how is the oil pressure?

I cannot make a video or sound recording because I do not own anything (not even a cell phone) to do this.

Is it while driving or at idle?
I notice the noise gets louder when the engine is under a load.
(e.g. when car is started and with foot on the brake and shifting between Park and Drive I notice that noise gets louder in Drive. No, not my transmission as I just put in a new rebuilt 1 year ago with no problems).

How does your oil look?
Is it at the correct level, is it clean or dark?
In between changes I do loose about 2 quarts of oil or so.
I have noticed a few times when there is a little more smoke coming from the tail pipe, but this is rare. I also use Valvoline Max Life.

how is the oil pressure?
When car is idling Oil pressure does drop to the lower end of the normal operating pressure, but at highway speeds it is well within the normal if not higher end. This is after car engine has been warmed up.

And, no, I'm not leaking oil.

My whole point here is that this goes against the so hype, great praise, almighty worship we hear about this GM engine.

Is this a knock you can feel? Or just hear it? Does it change with RPM, or is the change connected with speed. An example, you here it get faster and after the trans shifts it get slower again, or is it faster and faster as speed goes up. It could be a axle or a joint making the noise. Perhaps a bearing. Can you jack up the car and try turning the tire to see if there is play?

If your going threw 2 quarts of oil per change then your burning it. Do you see a puff of blue smoke at start up? Or do you see of smell oil smoke while driving?

No blue smoke when I start up the car.
Very rarely will I see blue smoke upon accelerating.
I cannot feel the knock just hear it.
I cannot tell if the noise increases with speed because when I speed up the noise seems to go away, or there is too much other noise going on that I cannot hear it.

If it does go away once past idle check your harmonic balancer. As they age the two halves can rattle a bit when the rubber between them degrades.