Hello

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I have a 2000 Excursion with the 6.8-liter V10 with about 72,000 miles on it. In the past month or so there has been a “rattling noise,” for lack of a better word coming from the front of the engine. My first thought was the noise was due to a bearing going bad in the alternator, water pump, power steering pump, or A/C but the truck is not having any electrical problems or over heating or other symptoms that would indicate any of those components going bad. Now I am thinking the noise is coming from the idler and tensioner. I bought the Chilton’s and Haynes’s auto manuals. When reading the trouble-shooting section the diagnosis indicates timing chain rattle and says replace the timing chain assembly. My question is when do the timing chains assembly need to be replaced on the 6.8 V10’s as a preventative measure?

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Thanks

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Allen

 

Allen aka c-how

First Welcome to FTE

Before you get all weirded out over the noise lets make sure it is not something much less dire.

There are many ominous noises generated by the exhaust shields, loose bumper hardware, front transmission access cover shield, small rock embedded in the serpentine belt, and even rocks, sand and gravel loged in the heat shields.

You can eliminate most of these by touch or eyeball. But it is dangerous to do without some help and being aware of the dangers.

You will need to be under the vehicle when it is runnig so you can be near the noise and see if it goes away when you touch or hold on to the vibrating things. This is safest over a pit like at the oil change house. If they will let you, do the under truck checking there. Wear a heavy canvas or leather glove and touch all the exhaust and access shields. If they are making a racket it will stoop when you hold it.

To make sure you don't have something embeded in the belt you will need a small mirror on a stick and a flashlight and someone to bump over the motor. Put a chalk mark on the belt so you can see where you started.

I had a small sharp rock chip in my belt and my neighbor decreed that I had the dredded piston slap and how Fords suck. Screw him and his stinking Chevy oil burner. Once I found the rock and tightened up my tranny shield you were in danger of putting your hand in the fan because there was hardly any way to know the motor was running.

Be carefull, check the simple things first and no, I am sorry, I have no earthly idea on the timing chains. I have a total of 9 V10s right now, some with fairly high milage and this has never been an issue.

 

To see if the noise is from the belt or something driven by it, just remove the belt and start 'er up. If the noise goes away, then there you go! You won't hurt anything by running it w/o the belt for a half minute or so.
mike