4.6 Knocking
 

Thought I would post this to get some feedback to find out what may have caused the issue I am having on my 02' 4.6 that is in my Explorer.

As I have seen in multiple forums many have commented of hearing knocks and ticks from their 4.6's. I guess I have heard a bit of knock and ticking here and there from this engine for many years but never really paid much attention to it cause it always seemed to be very intermittent and would go away. So within the last month I started noticing a more pronounced knocking from the engine but it was still intermittent. Well it kind of seemed to get progressively less intermittent which worried me. It would sometimes knock for a few seconds at start up and would stop but would come back if I revved it up, but would smooth out and stop knocking then start again. Anyway I suspected rod knock cause that is what it sounded like and ultimately ended up being. Yesterday I put it up on the hoist pulled the pan. All of the rods where nice and snug except for number 8. When I pulled the cap an mic'd the journal it was measuring around 2.046 and 2.062 90degrees out from that measurement. So it was out of round also. The journal on number 7 measured in perfect spec of 2.08. The engine has around 115k on and has been well taken care of.

Does anyone know if this is a problem with these engines or if there is something that may have caused this that I need to look for. My plan is to yank the engine next weekend and have the crank ground and install oversize bearings but I want to make sure if there is some other underlying issue that could have caused this.

Thanks,
EJ

No really common issues that I have seen on these engines. #8 is the farthest from the oil pump so it would suffer damage first I suppose.

Is the pump pick-up clean of sludge? Is the bearing trashed?
What weight oil did you use?

Is the pump pick-up clean of sludge? Yes seemed to be

Is the bearing trashed? No not too bad actually but there was metal flaking, I've seen alot worse.

What weight oil did you use? I changed it occasionally but usually it was changed at lube shops so god only knows.

I know I have since read that always have to use 5-20 and best to use motocraft filters so I will definitely make sure that happens once I get it back together. I ended up buying a reman crank for $190 so I am going to install that.

Pulled the motor this weekend. What a nightmare! I have pulled several motors over the last 20 years and that one was by far the worst one I have ever dealt with.