Detonation or Timing Chain rattle?

[DDEBEXP]

For awhile now I have heard a noise very much like that is described in the timing chain TSB. I have the 4.0 SOHC. Recently I did a sort of tune up. Changed the plugs, fuel filter, oil change with Lucas (is Lucas worth it?) and Seafoam through the vacuum line and gas tank. All of a sudden, I don't hear that noise anymore. I used to be able to hear it all the time but I just don't seem to hear it anymore, at least on the hot engine. I have not really payed attention to it when it is cold but it used to be really loud and now it is definitely not noticeable or gone. What is your opinion. Was I getting detonation around the same RPM as the rattle was supposed to occur or did I just somehow quiet the rattle down? Thanks

 

[CHRISXPLOR]

it sounds like the same thing i have! so the seafoam worked??? nice got to try it!

 

[Russ in CT]

Obviously, Seafoam isn't going to fix a bad timing chain (or tensioner), so if the 'pinging' sound is gone, then it must have been actual pinging (which Seafoam could have fixed, by removing carbon deposits in the combustion chamber).

But before you call it 'fixed', keep the radio volume down and keep listening, make sure the noise is really gone. Maybe you had two problems, actual pinging and timing chain noise masquerading as such, and the Seafoam has fixed one, keep listening for a while to verify you don't have the other.