I don't have the noise problem in my truck, in fact, I don't have a lot of the problems I have read about on this forum with my truck, so I consider myself lucky.
However, I did own an '03 Mazda Protege before my truck, and it had the exact noise on startup that everybody is speaking of in this topic.
Apparently in the '03 Protege they tried something new, I believe it was variable timing, if I remember right. They claimed the car never needed to be warmed up because of this variable timing. Every time I started it up, and as I drove and hit approx. 2500-3000 RPMs, it sounds like a deisel motor. But it was never an issue with my car for the 2.5 years I had it, just a noisy motor.

 

I honestly think there sould be a comprimise between how the problem is solved, a bit of your theory and greythings. I think DC should replace the motor in your truck and send the "noisy motor" back to the factory where the engineers can study it. That way you have a new motor and then it can be played with to find the problem. I know BMW and Honda will do that. I actully agree with greything on this one, but a whole new truck isnt neccessary. Money wise it would probably be cheaper for DC to do it that way than have you come in and out with engine teardowns. Your right tho when they figure it out it will help everyone, just replacing the truck would leave your old truck out in the system with the same problems as the next person may not care about the noises. I am so glad I didnt get the HO motor as it seem more of the HO owners are having the problems. I didnt get it because they didnt have a HO truck in the blue I wanted with the towing package.

 

UPDATE: The dealer had ordered new tappets (similar to lifters) for the entire engine last week and today they were all replaced. I'll know tomorrow if the noise has gone away.........

 

Waiting for those results. If that fixes it I am making an appt in the dealers service dept. really soon.

 

UPDATE: After starting the truck yesterday after it was put back togther and again this morning they claim it is no longer making the noise. I'll be picking it up tonight on my way home. If it sat all day today (since this morning) I should be able to tell myself when I start it but I won't know 100% until tomorrow morning when I get in it to go to work. I'll post for sure what the outcome was tomorrow morning.

 

FINAL UPDATE...............
It appears the noise is gone. Let me explain further. Before it went in I could here the clackty/clack at startup while sitting in the truck with the windows up and would last for a few minutes then go away. Now, if I want to hear anything I have to get out of the truck and stick my head into the passenger side front wheel well to hear a very, very muffled version of what I used to hear. And you really have to listen for it. I have two final theories.
1. Due to the more aggressive cam lobes in the HO motor, it is bound to make a little more noise than a standard 4.7. I beleive I read this somewhere also.
2. Next oil change I am going to try 10w-30 oil instead of the factory recommended 5w-30 that I have been using and see if it sounds any different.

I asked if a TSB would be developed due to all this, the answer I got was "we don't know, Chrysler is real funny on how and why they produce those." If one comes out and I can get my hands on it I will surely post it here.

All in all I think the problem is gone. Hopefully I won't be updating this thread anymore with "it's back," but you never know and it wouldn't surprise me. I hope this will help any others that are having the same noise I was. Remember, I posted the sound bites I had on this forum, just read through this thread and you find the link to where it is.
I have attached a cut-out copy of the workorder for my truck in regards to this issue. The name you see, Jeff Price, is the regional Service Manager for this particular area of Maryland. All 16 tappet valves were replaced even though they saw no abnormal wear on any of them when they were inside investigating. Figured the heads are off lets just replace them all.

[IMG]local://upfiles/20642/78B33B54E9CC4DC8BA27638EAA512A7D.jpg[/IMG]

 

I've been reading through this thread for the past few weeks with all the comments and your patience in dealing with getting the noise problem fixed. My dad had similar problem with an older Chrysler 318 engine. They also discovered it was the lifters. He never fixed the problem, but the truck ran for 4 years like that. I'll keep this post in mind if I ever have any problems with my 4.7L on my 2005 Dakota.

 

when i start my truck it makes this thunder-like noise and then it settles to a deep tone like a lion growling. then i put it in drive and it sounds like nascar breaking loose. i will look for a TSB on this and post it if i find it. anyone else have this problem? my dealer said it COULD be the FLOWMASTER SUPER 40 DUAL SIDE EXIT NO RESONATOR STRAIGHT CAT-BACK system~ but no one is relly for sure here....oh well

 

That’s one way of drowning out the abnormal engine noise! You can even drown out a flat tire with a good sound system.

 

im sorry...i didnt realize flat tires were loud?? i could have thought of lots of noises besides a flat tire... keep thinking