Im hoping some of you gurus around here are familiar enough with timing chain rattle, or is this coming from my tranny. I havent been on the board in years... wife, kid, life changes. Background: Built 4.0sohc, xcharger, SSM heads/cams, Wiesco pistons, water/meth, arp studs and rod bolts... etc,etc. Close to 490 rwhp with a 60 shot of gas. Anyhow.... since the motor was built in 2010, with all new timing components, I have not raced or took it to the track. Weekend driver these days ... once in a while I will blast it down an old country road to put a smile on my face. Recently developed a rattle that sounds similar to a loose heat sheid or spark knock. Sounds like its coming from my shifter (mdo5r1hd 5 speed) area or in front of it. Removed the console and boot to see the top of tranny. Sound is louder in deed. Two mechanics I trust rode with me and swear its the tranny. BUT.... I know this engine. I know the timing chain issue and it only does it between 2500 and 3000 when warm. No start up rattle which rules out the hydrolic tensioners. No rattle at idle, no rattle reving. Only under load at the above rpm range. Which im afraid is the timing chains. Approx. 25k miles on the new upgraded timing kit from 2010... oem ford of course. Those are easy miles considering. Had it up on a lift today to try and replicate noise... of course, no load, no noise. My thing is, could the upgraded version timing kit wear out in 25k miles? What could be in the tranny that would make that noise, at that rpm, that sounds like a loose bearing rattling around if its not the chains. I have been reading for months now about the timing chains and different tranny noises. I would hope to think, if its the chain, its the front leaf spring type tensioner on the balance shaft chain. I DO NOT know what guide failure sounds like. What Ive heard on youtube, they pretty much do it at idle and its a loud clatter if its the guides. This is more of a chain mesh type of sound. Tried to record it to no avail. To much background noise. Its loud enough that i can hear it bounce off cars next to me or the center wall on the freeway. Sounds like its coming directly from underneath the truck. Sorry for the long post... the days of having money to through at this truck are long gone. Thats why I`m seeking some advice before proceeding. Thank you for your time.

 

Well if its "engine" RPM specific then it would be an engine rattle

Trans input shaft does spin at engine RPMs but only when clutch pedal is up, if "rattles" goes away when you push clutch pedal down then yes transmission issue

 

Yeah, thats what i figured... Thanks for the reply.