I have a 2006 STX 4x4 4.6l and there is a knock in the engine. It starts right after start up but seems to go away as the truck warms up. After the truck is fully warm the only time I hear it is when I stop at a stop sign or something as I take off I hear it until the truck gets up to normal RPM then I don't hear it anymore. I have been told it may be a rod and I have been told its nothing to worry about. Any help would be appreciated.

 

What are you using for oil and oil filter?

 

Not real sure I didn't put it on but I know it's blue I can't see the writing on it though

 

And the oil is 5w-30 I do know that but I don't know what brand ( I just bought it from a dealer 3 weeks ago)

 

You just bought it? Did you hear it knocking before you bought it? Does it have any kind of warranty?

I have a feeling you got taken to the cleaners.

 

You should be using 5w-20, just so you know.

 

The 4.6 isn't that critical, 5w30 is acceptable. Be nice to know if that blue filter is made by Fram..........

 

If the oil filter is causing the problem it would be because the oil is bleeding out of the filter (certain filters have no bleedback valve) while the truck is shutdown. Then when the truck is started the filter has to refill with oil, this causes a void in oil pressure and you can experience a knock for a few seconds. If you are hearing a knock while driving then I would suspect something else is causing the noise. I imagine the people that told you not to worry about the noise are the same ones that sold you the truck... Go buy a cheap mechanics stethescope, start the truck cold and while it is making the noise move the probe around to various areas of the engine, oilpan, front cover, cam covers, etc. and determine where its the loudest. Another tool is, while its running and making the noise remove one fuel injector connection at a time and listen for the noise to diminish or stop completely. If you find that one particular cyl does respond with a drop in the noise or it goes completely away then the chances are it is a rod bearing on that cyl.

 

any updates????

it helps the community when you have a problem and get it resolved to report back if it relates to the f150. i know its a lot to ask. it helps the next sorry sap from having to go through the same head aches and possibly save $$$. most people on here are here for answers. if everyone just asked questions, all the threads would be useless and the site would be like **** on a bull....