Ford knock

[Trav]

As some of you know from previous post i have a Ford 5.4 with noise that sounds like a knocking from the bottom end.
It didn't sound like a rod or main bearing more like a piston pin and sometimes like a lash adjuster it seemed to change tone sometimes.I was trying different filters and different weight oils to no avail.

Today i was under the truck with it running and heard this knocking pretty loud this time (cold temps)it sounds like its coming right from the cat.
Sure enough Ford has a TSB about knocking cats and makes a sound deadening kit.They say not to replace it for this issue.
Problem is the kit is almost $400 online i can get new Eastern cats for this.
Now i know what the noise is exactly i wont bother doing anything with it as it clears up for the most part when the engine is at operating temp.

I hope this may help anyone experiencing this knocking with a 5.4 The TSB does not mention the Expedition but it is exactly the same condition.


TSB 04-20-6 TICKING OR KNOCKING NOISE COMING FROM THE CATALYTIC CONVERTERS
ISSUE: Some 1997-2003 F-150 vehicles equipped with any engine, and 1997-1998 F-250 LD vehicles equipped with the 5.4L engine, may exhibit a ticking or knocking noise coming from the catalytic converters. The noise may be described as sounding like a diesel engine. The condition will be present when the vehicle is in gear at idle only, and is more pronounced when the vehicle is stationary, such as sitting in a drive-through line. The noise is normal, and is created by engine pulses being amplified through the light-off converters.

 

[chubbs1]

Have you used different filter brands with the oil changes you did? sometimes that will be the problem. Cheap to try[out before you spend a lot of cash. Although I feel deep down it is a problem with the CAT.

 

[OVERKILL]

Interesting! I remember reading this TSB as well.

Personally, I'd slap a set of Magnaflow high-flows on it and use this as a time to rig up a true-dual setup

LOL!

 

[Zaedock]

I may have posted this before too.

I have an '03 5.4L FX4 ex-cab. I hear the knock every once in a while and have for a long time with no ill effects. I think the solution was to wrap the cats, but it doesn't bother me enough to bring it in for that.

 

[Trav]

Yep with no difference at all at least now i know why.The noise is not in the engine at all its the cat 100%,i can change the noise distinctly by pushing a crowbar against it in the front.Its not the shield the unit is tight and rust free.

I wont bother with it any more,i have peace of mind now.It can keep knocking/ticking all it wants.

 

[SuperDave456]

Very Interesting. I will have to try this with my 1998 V6 F150. Same type of noise, same place, different weights and filters result in no change.
It could be the cat.

Thanks for the info.

 

[demarpaint]

I've heard the older Fords knock from a pollution pump, it drove me nuts for a short while. IIRC it's called a Thermactor Air Pump, AKA smog pump. I had one knock while it was cold.

 

[SZR48207]

My V6 F150 probably makes this noise. I know the fuel injectors are pretty loud, but I have heard a "ticking" noise under the engine area and figured it to be from the exhaust. Like the other guy said, why not put on aftermarket exhaust and make it worthwhile.

 

[Trav]

It has a new stock cat back OEM exhaust. Some vehicles use positive back pressure for the EGR to operate properly,i just don't feel like getting into some sort of issues and the expence on a SUV that basically just chases parts and building materials in the winter months.

 

[OVERKILL]

Originally Posted By: Trav
It has a new stock cat back OEM exhaust. Some vehicles use positive back pressure for the EGR to operate properly,i just don't feel like getting into some sort of issues and the expence on a SUV that basically just chases parts and building materials in the winter months.



My muffler split at the seam, so we salvaged the tailpipe part as well as the part before the muffler (hacked off the resonator and replaced it with a 3" chrome piece) and put on a Magnaflow.

Truck sounds awesome.