Thanks for the tips!! I didnt even think of spraying down the studs overnight. Im on my way outside right now!! Thanks for the advice!

 

just curious...did the knock go away after the engine warmed up...I have the infamous cold engine knock on my 01 expy, i have been told it's piston slap, bad cat's or a leaky exhaust.. please let me know if changing the gaskets helped...truck runs great..but that early morning knock makes me crazy

 

Ok replaced the mani's and gaskets yesterday and wow what a difference. The truck seems to have more power, and runs alot smoother. Now that the knock is gone, I do hear a slight tick but its nothing major.

 

You'll get more help if you start a new thread. Include the year, engine size, and how many miles it has on it.

 

I didn't want to start a new thread because there are several that already go into the cold start knock...I try to sort through them and match it up to the noise I'm hearing...it seems there are many differant opinions on what actually causes the knock sound...here's some more info...2001 expo, 109,000 miles. recently had all plugs changed, have tried every combo of oil, 5-20,10-30, and only use motorcraft filters, but for 5 minutes at startup there's that loud knocking noise, had it since 89,000 miles, i got 4 differant answer's from 4 mechanics, dealer 1 said piston scuff, dealer 2 said piston slap, private mec. said cats are bad, private mec. 4 said leaky exhaust, once truck is warm, engine purrs like a kitten, but those first 5 minutes...it's almost embarrassing driving down the streets...I've read just about every thread on the cold knock...I'd like to get whatever it is fixed, but just don't know what is causing that noise...thanks again

 

sorry...forgot engine size,,,5.4L

 

Get yourself a mechanic's stethoscope, it will help you to pinpoint the noise and answer your question.

Harbor Freight Tools

 

Your issues may or may not be the same as the person who started this thread. Yes, there are many threads involving similar symptoms that you are experiencing. The suggestions and solutions given in the various threads are tailored to the person that started the tread. It is also discourteous to the person that started the thread to have it hijacked.

 

Ain't you glad you didn't fall for eallanboogs advice and immediately tear the engine down and start looking for that spun rod or main bearing? Man...he was all over that diagnosis... according to him it was certain death!

 

Based on my many years of experience eallanboogs diagnosis was nearly spot on. I had nearly the same described noise in my 98 Expedition and before I removed the pan I checked for noise with a stethescope, located it at the rear of the engine and pulled the pan. The #8 rod bearing had spun. Now a 98 4.6 DOHC from a Mark VIII engine is going in. ...

 

nearlybeaing the operative word? By using a stethoscope, you were 'spot on'. Suggestions or opinons are one thing on here but to sound so sure could mislead someone. There are tons of great info in this website...I use it all the time, but it sounded as if there were no other options according to his statement...once again, my opinion of what was being said. I could be wrong.

 

I have a 01 Super Crew 5.4, seems to have a knocking sound on the passenger side. I listened closely and the noise is loudest toward rear of head and at the catalytic converter. I do see that the rear stud is broken on that side exhaust. I am very anxious to get my parts for the re seal. Just wandering if this sounds similar to what you faced?

 

Get a mechanic's stethescope and check all around the area the noise seems to be coming from. You will be surprized at all the noise you hear. You have to narrow it down to the location as best as possible and perhaps pull the pan and inspect to be certain. It could be an exhaust noise only as they can be pretty loud under a load.

 

Mel

I re sealed the exhaust manifold, the bolts were broken and there was evidence of a leak. The Knock is still there it sounds to be bottom end. I have checked it with a mechanic ear and It has been hard to narrow down. What did you find when you pulled the pan? The knock has been there a while and it isnt as bad as rod knocks I have heard before.

 

Mine had a spun bearing on #8 rod and a partially spun bearing on #7 rod. Not good news at all. I think you should start looking for a good used engine, just as a precaution. Mine was very quiet even under a load. I just sounded like a lifter gone bad.