Rattle - Flex Plate Bolts?

[stableboy]

Hi,
Local garage put in a boneyard 4.0 in my 2003 FX4 after the cam chain tensioners grenaded. Moved since then and after several weeks a rattle developed - sounds like passenger side rear. It does NOT sound anything like the tensioner rattle before it self destructed and pretty much disappears once hot. Engine runs and sounds great otherwise. Exhaust system is tight. I've heard similar sounds from loose flex plate bolts. Is there a simple way to check? Going under it now to see if there is a dust cover/inspection plate on bell housing. Thanks!

 

[RonD]

Welcome to TRS


From description it sounds more like an exhaust rattle.
Flexplate issue wouldn't change with heat and you didn't mention noise changing with RPM which flexplate noise would do.

Exhaust metal expands as it heats up, so rattles can go away.

When system is cold take a rubber mallet or ?? and "tap" firmly on all exhaust components.

 

[pjtoledo]

flex plate bolts, at the crank or TC, when loose will/can rattle at startup or whenever the rpms are low as the crank speed is not steady then. they should stop as soon as the rpms increase and the crank speed is steadier.