06 ls enigine noise

[bobbyward]

On real cold days i hear a thump coming from the front of the engine , any idea what it might be ?

 

[joegr]

Does another neighborhood cat disappear everything this happens?

Otherwise, bad belt, bad belt tensioner, bad motor mount, wrong oil, ...

 

[bobbyward]

no cats, i could only wish, just put on new tensioner idler and belt and etc.

 

[G-RELL]

when, where, how often... need a bit more detail than a noise from the front...

a video works best

 

[bobbyward]

only on days it gets to single digit weather which we don't have often. a few seconds and its nice and quite again. maybe it has a cam tensioner making that noise, not sure whats up with it .

 

[joegr]

My damper pulley (well the outer part of it anyway) wobbles when it is cold. It seems to be a [known by Ford] issue with the rubber shrinking between the inner and outer parts of it. For me, it causes squeaking as the belt tensioner oscillates trying to compensate for the wobble. Maybe one day I'll change it, but it won't be with a $700 new one.

Anyway, when you start the car cold, have someone with a flashlight look at the damper and see if this is really your problem too.

 

[All2kool]

My damper pulley (well the outer part of it anyway) wobbles when it is cold. Maybe one day I'll change it, but it won't be with a $700 new one.

When you said $700 for a Pulley, I was shocked. Just for giggles, I went and checked EBay. What is the difference here, other than the engine spec?

 

[joegr]

My guess is that it just has to do with the quantity made. You couldn't get these at all for a while (while they were correcting their problem with dampers), then they made a batch for repair parts. Apparently it was a small batch and they are trying to get their cost of retooling out of it.
The 3.0L was used on a lot more than just the LS, T-bird, and S-type, so its tooling cost is spread out a lot better.
(Again, this is just a guess, there doesn't seem to be anything special about the 3.9 damper.)

 

[All2kool]

...there doesn't seem to be anything special about the 3.9 damper.)

Which makes a person wonder if you could use the 3.0 on your 3.9?

 

[joegr]

Which makes a person wonder if you could use the 3.0 on your 3.9?

You may want to look up what a damper does and why it is there. It has to be "tuned" for the specific crankshaft/engine that it is going on to do its job.