Ok so my car started slowly knocking and i drove it about a half mile to park it and it gradually got louder. I lost oil pressure for a bit. So i parked it and came back the next day. The knocking still continued but as i let it run for a few seconds the oil pressure built back up to normal. The car sounds like it runs fine besides the knocking sound. Its not sputtering or anything so if you took the knock away it would sound perfect. I took it down to a shop and they said I threw a rod. I feel like they didnt take the time to pull anything off and check it out. Does this sound like I threw a rod? Just from driving then it slowly doing it then gradually building up to a loud knocking noise. I thought when you threw a rod the car was undrivable. Please any suggestions. I am taking it to another mechanic to have it looked at if you all agree you dont think it is a thrown rod. thanks guys

 

car is drive able with a spun bearing. oil pressure wouldn't come back up to normal though.

 

if you actually threw a rod, you would know it. the engine wouldnt run at all if you did that. sounds more like you spun a rod or main bearing, but its more likely you spun a rod bearing. if you know whats good for you, you wont run the engine anymore. i mean, not even long enough to put the car on a trailer or something. the longer you run it, the more damage you will do. as of right now, youre looking at a set of bearings, and maybe some crank/rod work + labor. if you keep running the engine you'll be looking at a helluva lot more damage (new rod(s), bearings, crank, or even a new block/engine).

what year is your car? and how many miles? some LS1's have problems with the oil pump.

 

A knock in the motor from the bottom end usually mean a worn out rod bearing. And you shouldn't even start it again. As stated above everytime you run it you hurt it more, spreading metal chips throughout the motor into all of the other internals.
Some mechanics use these terms interchangably. "thrown a rod" "spun a rod" "bad rod bearing" meaning that a rod bearing has to much clearance and is knocking.
"thrown a rod" = rod bearing set up and broke the rod generally punching a hole in the block or pan.
"spun a rod" = having the bearing actually stick to the crank and spin inside the connecting rod.
"bad rod bearing" = rod bearing clearance increased to the point that it knocks against the crank as the motor turns.

 

that happened to me...spun rod bearing....

 

time for rebuild.