Rik

[rwajeep]

I have a 2003 TJ with 2.4l engine. It has 35000 miles on it. It has developed a knock. Prior to the knock I had drove it about 25 miles going 68-70 mph in 4th gear fighting a strong head wind. During that drive, and after getting off the interstate and driving home there was no knock. A couple of days later, when I started it up, it had a definite knock. I shut it off checked the oil, down about a quart. Started it back up added oil and the knock quieted down but did not go away completely. Driving down the road at 45 or so I don't hear it. It had been 2000 miles since the last oil change. The noise is definitely on the bottom end toward the rear of the engine. I cut the oil filter open, saw a couple of brass/copper flakes in the pleates. I pulled the oil pan thinking I might check bearing caps, push rods, etc., not realizing I wouldn't be able to see anything as I didn't know about balance shafts. The oil pan and oil were clean. I put it back together and took it to the dealer for their opinion. They put on their listening muffs and probed everywhere. They think the noise is coming from the clutch. Doesn't make since to me as it quieted down when i added oil.
What are your thoughts? I have driven it about 50 miles since the knock/noise started. It is noisier when I first start it since it has been getting colder.
Thanks for your thoughts.
Rik

 

[Utah_jeepster]

Locating and defining a knock is a hard thing to trace down, especially over the net. First off the 2.5 and the newer 2.4 are notorious oil eaters. This is one engine that you will need to check every other fill up on oil levels. Now they do have a thrust washer in the crank set up, this could or could not be why when you added oil it quieted down. I would start adding a 1/2 bottle of Lucas oil treatment with every oil change. I have found this helps the 4.0L when I am on the trails, and the guy who turned me on to it ran it in his 97 2.5L for the same reason. Start and stops over the whole day can produce ticks and knocking noises at start ups.
Now the last thing you said was you found brass/copper flakes in the oil filter, the only copper/brass parts are the valve seals(some one confirm or correct me here). small flakes are usually nothing to worry about, unless its a constant stream, every oil change.

 

[luis]

I have a 2003 TJ with 2.4l engine. It has 35000 miles on it. It has developed a knock. Prior to the knock I had drove it about 25 miles going 68-70 mph in 4th gear fighting a strong head wind. During that drive, and after getting off the interstate and driving home there was no knock. A couple of days later, when I started it up, it had a definite knock. I shut it off checked the oil, down about a quart. Started it back up added oil and the knock quieted down but did not go away completely. Driving down the road at 45 or so I don't hear it. It had been 2000 miles since the last oil change. The noise is definitely on the bottom end toward the rear of the engine. I cut the oil filter open, saw a couple of brass/copper flakes in the pleates. I pulled the oil pan thinking I might check bearing caps, push rods, etc., not realizing I wouldn't be able to see anything as I didn't know about balance shafts. The oil pan and oil were clean. I put it back together and took it to the dealer for their opinion. They put on their listening muffs and probed everywhere. They think the noise is coming from the clutch. Doesn't make since to me as it quieted down when i added oil.
What are your thoughts? I have driven it about 50 miles since the knock/noise started. It is noisier when I first start it since it has been getting colder.
Thanks for your thoughts.
Rik

Could it be your lifters? I know they could make a knocking noise when they aren't getting oil. It would make sense that they would have quited down when u added new oil. And as for the metal shavings I would set a magnet in the bottom of the pan and see how much metal actually builds up after a set amount of time.