99 Mounty 4.0 V6 Timing Chain?

[RichCresci]

I have a 99 mounty with the 4.0 SOHC and it makes a god awful grown when you start it up. From what I understand its either the timing chain or something in the valvetrain. I had a mechanic tell me that this particular engine has some crazy rediculous timing chain setup and its impossible to change. He said you practically have to pull the motor to change it.
1. Is this true?
2. If so does this apply to all the 4.0 SOHC engine's such as the one in the 3rd gens?

I've heard this "growl" in other explorer/mountys before. Does anyone have any experience with this?

 

[estell]

I don't know about the growl, but if it is a rattle then it could be the tensioner(s) for the timing chain(s).

I just went through a replacement of the tensioner on the primary timing chain in my '02. Your '99 may involve the camshaft chains too.

If so, the engine does not have to come out unless the tensioner on the rear chain is broken. Apparently that is rarely the case.

There is lots of reading on this issue.
http://www.explorerforum.com/forums/showthread.php?t=163298
http://www.explorerforum.com/forums//showthread.php?t=135048