Greetings bretheren,
I have a question regarding my truck. I have 35998 miles on it. I have a knocking noise in the bottom end on initial start when cold. Does not seem to happen when weather is warmer. After fast idle comes off (15 sec) you can hear a repetitive knocking from the motor. I have read many posts on the internet and have been in the car business for 25 years, its not a lifter or a vvt. Its in the bottom end. I suppose the questions for me is the maintenence. YES is the answer. ALL done every 3000 miles. Has anyone else had this occur and what was the outcome? I have dropped it off at the dlr now and awaiting results, just wondering what anyone else has experienced.

Thanks in advance.

 

Could it be piston slap?

 

Sounds like it to me, possible wrist pin. Just wondering if anyone else. My guess is dlr will tell me normal and then all the wear from cold starts will cause implosion at around 80k. Thats what worries me.

 

Now this may sound strange, but the dealer did show me a technote. have you switched from a ford motorcraft oil filter to something else? If so, that is the problem.

 

the check vlv failure on filters usually only affects the timing train noise...but I guess it could be a factor described above.

why wait until your 2 miles from end of warranty to take in?

 

I thought 2006 models automatically got the 100k powertrain warranty?

 

No one must buy the warranty, changed in 07. But I did get 10000 off sticker and 0% financing.

I do not use ford oil, the brand of oil simply cannot cause or fix any type noise in an engine, now the viscosity could. However at such a low mileage it should not matter. I can understand high mileage cars with substantial wear and using a too low or too high causing a noise. This has been ongoing for all winter season.As to why take it in now? I havent had any problems to speak of. I have started many F150'S while I have had them in my posession (at our shop) and some have had it and some not. I am very busy and was waiting until the end before I took it in, simply to see if there was any thing else wrong (my drivers seat queaks) Kill two birds with one stone. This is a great truck, narry a problem as of late and still is.

I do not have motorcraft filter on it. One of my vendors takes care of my oil changes and im sure its not. As a former service manager of a dealership im aware of the filter and its check/bypass valves to prevent bleed out of pressure on an engine.This knock starts after fast idle and then continues for around 4-5 minutes until I drive off and engine reaches operating temp. The check valve (if this is creating the noise) should clear up in just a few seconds, would you agree? And it does not sound like a timing chain rattle. You can hear it inside the house when its in the driveway warming up.

I guess I will find out today the mystery. Its 23 deg here this am and Im confident it will make the noise again. At least I was able to pull a few strings and get a 2008 Expedition EL to drive while its in there!

Will post results here for reference.

 

Called me and said the usual, it didnt make the noise. Absoulute bs I tell ya. It does it every day. Stay in the loaner cause we still are fixing the seat, we will try again tommorow morning.

 

I have an '07 F150 with the 5.4 and a '04 Explorer with the 4.6. Both of these cars are very noisy on start up on a cold morning. I have read several posts on here about the engines making alot of noise on start up. Maybe what you are hearing is normal.

 

OK, went Friday to pick it up, told me no noise. We went to the parking lot to walk around (for dents and such) I started it while we were talking and low and behold there it was. It was there all the time im sure of it. Anyway, shut it off and waited for the tech to come out. Thinks its the egr valve of all things. I have never opened the hood when the noise was going on. This truck does not have a hood unsulator and the egr valve sits on top of the motor echoing in the engine compartment like a loud lower end knock. Waiting on the egr valve to come in and we will see. In 24 years in the car business I have never heard an egr valve knock, (and neither have they for that matters- so they say)

Will keep posted.

 

Picked it up, new egr, no noise as of yet. Runs much quicker for some reason. Mabye my imagination?

 

my 4.6 in the Mustang also is a little noisy on startup. EGR has big effect on carb vehicles...not so sure how it affects EFI

you said your hood doesn't have the liner? wierd...mine does

 

Nope when I bought it, I was just looking for a basic truck, no frills 4x4 or anything. All I was ever after was a truck/black/cruise control and ac. STX fit the bill just fine. Got the nice rubber floor you can wipe out and not worry about carpet. Did get the super cab for my kids to ride in the back. I dont beat it to death either, had it two years, still shiny as the day I brought it home, not a scratch or dent on it. I have added a sliding rear window (tinted) and tinted the windows. Whole truck is black looks nice. Took the stx emblems off the bed and have a US ARMY sticker in the rear window. Functionality for me with a reeeeal nice looow payment. Will be paid for in a few months.

 

I have a 2006 Screw with the 4.6 and I have a knock heard when idling, after initial startup. Took it to the dealer and said noise heard at idle and the service advisor heard it to. The tech wrote road tested noise not heard. Well no kidding!!! I don't hear it while driving either. Anyway the dealer said ford won't pay them to look around and try to find where its coming from. So I still have this annoying knock that the dealer has no idea where its coming from.

Have you heard the noise anymore since the EGR was replaced?

 

brought mine in for a knock on my 4.6. they said it is normal and my in-laws tahoe makes the same noise. maybe they aren't lying.