I have 2010 Silverado with 5.3 Been hearing loud ticking and clanging noise from transmission bell housing area. brought it to mechanic, they disconnected the torque converter to see if it was in transmission or motor. Still making the noise with it unhooked, Flywheel has no cracks and is tight. Was told most likely a main bearing was going bad! Anyone had this kinda of problem?..only have 115,000 miles on this truck!
I would guess a failed lifter on that particular engine, but the sound would come more from the engine than the transmission in that case. Does the sound increase in frequency with rpm? How does the oil pressure look?
What you might be hearing is AMF lifter failure.
Yes, im getting a second opinion from a different mechanic before i decide if i replace engine or not. He is busy like all mechanics but did listen to the tapping noise, and mentioned maybe a failed lifter…even though sound is louder and more noticeable at the back and bottom of engine. The sound is twice as loud in morning when engine is cold…then does quiet down a little after engine warms up. But good oil pressure, stays around 35-40 lbs. No major oil loss, less then a quart between oil changes. But as you mentioned, like every other 5.3…the lifters tapped on cold start up, but would always go away after just a few seconds. I guess a valve job or head replacement is better than new engine. But either is going to be expensive!!! And only 115000 miles, thats what sucks!
If it is a failed lifter, they’ll have to pull the heads to get to the lifters. If you go that route, you might consider going ahead and getting rid of the AFM altogether by installing non AFM lifters. I believe you’d have to install another cam also, which might not be a bad idea anyway since a failed lifter can wipe out a cam lobe. Something to investigate, anyway.
But, yeah, let the shop check it out. If it is a bottom end knock, then it’s rebuild time…or swap in a 6.0 without AFM…