ticking or knocking

[smooththg6969]

hello guys I rebuilt my northstar a few weeks ago (cracked block) you can find my post under the screen name smooththg69 for some odd reason I cant post with that account any more. well anys way ive been driving the car for about a week or so and have strange tick coming from the the bottom of the engine some time its there and some times its not I cant hear it while in the car but its audible out side of the car. I also have a leak at the rear main seal. so today before work instead of me putting oil in as usual to top it off I put in a qt of atf because I also have a lifter tick that comes and goes well to my suprise got to work left the car on to listen for any noises and they where all gone . get off of work go to gas station and there back.I dont know what is causing this . Im thinking its a oil pressure issue so im going to take the engine out change the oil manifold since the one on there didnt look too good to began with and change the rear main seal and oil pick up tube And see if that fixes my problem. Im thinking the the manifold is not sealing properly causing a pressure difference which is not being picked up by the oil sensor if this doesent help Ill ebay it and look for a gto Any thoughts on this? you can find my previous posts here

http://www.cadillacforums.com/forums...i-screwed.html (Am I screwed ?)

http://www.cadillacforums.com/forums...-progress.html (pics of the progress)

http://www.cadillacforums.com/forums...ion-rings.html (reuse pistion rings?)

[97STS4ME]

Could be any number of things. What parts of the bottom end did you replace when you rebuilt it? Pistons? Bearings? Rods?

[smooththg6969]

well I reused the pistions and rods and changed all of the bearings its coming from the end towards the tranny but not the tranny Im going to double check the flexplate bolts when I get a chance. but when I bring the rpms up it seem to go away.