Well, I started another thread on here asking about putting a new PCV valve in, which I finally did. I've had a slight knocking when I first start up my truck that eventually seems to go away once it's at normal operating temperature. I was hoping changing the PCV valve might help but unfortunately it's still knocking when I first start it up. What do you guys suggest I try to get rid of the knocking? I use 5W30 oil which is recommended. That's what I've always used. Should I try going a little heavier starting weight like 10w30 since the problem only seems to be when the engine is cold? Should I try sea foam and see if that helps? Maybe I have some carbon buildup in there, I don't know. I just changed my oil about a month ago so I guess I'd have to wait a while before going the sea foam route. Anyway, any suggestions would be appreciated. Thanks.

 

Did it start knocking after the last oil change ?
What oil filter are you useing ? It may have a bad anti-drain back valve.

 

It always knocked just a little right after an oil change but then it would go away. This one hasn't gone away since the last oil change about a month ago come to think of it. Should I basically just try another oil change and see what happens? I always use the motorcraft oil filters since Ford recommends them. Never had a problem with one before. Thanks.

 

If I decide to do another oil change just in case it's a bad filter, should I continue using the 5W30 or should I give 10w30 a shot? I've been using 5w30 high mileage oil but someone told me recently that high mileage oil is bad for the seals. Is this true and if it is would it be OK just to go right back to the standard oil or should I just stick with high mileage oil? I've actually been using it for a couple of years now. Thanks.

 

hey at least you dont have the 04-05 f150 knock, i got it but im not worried, my 5.4 knocks all the time, sounds like a diesel

 

Do you guys think I'm maybe making too much of this? I just changed the oil filter a little while ago to at least eliminate that possibility. You can still hear that slight knock at start up. Goes away when warmed up just like before. I could try the seamfoam thing next although I probably should've tried that first since you have to change your oil right after it. Maybe I run a good fuel system cleaner through it and see what happens.

 

my 2000 ranger knocked on start up when it was colder out side (fall/winter) but the knock quickly disappeared, so if its the same as what mine was i wouldnt worry about it

 

mine does the same thing, when it warms up it goes away, shoulds like a knock, but with a liquid swush to it, i was told could be a lifter, but i put some stp in it and it didnt work right away, but the longer the oil is in the engine (between changes) i notice it gets less and less, so yea good thread dude i am gunna monitor this one, o yea, i did the whole seafoam thing.... didnt help so do it just for the carbon, but it wont fix the problem