[Tatianna El]

Just purchased a used 2007 T & C 3.8 v6. Very pristine inside. You can see it was kept well with 93,000 miles. It was giving a knocking sound when I first crancked it up but as it warms it got quiet. So I decided to do an oil change. I changed the oil filter, all spark plugs and wires. I then added some STP oil a real thick honey like substance. (My mechanic suggested it). The knocking got even more quiet. Then it came back. So after watching a few YouTube videos I learned that I may need to check out the rod bearings which required me to drop the oil pan. My mechanic hesitated to do this and suggested I got a new engine which by the way I cannot afford so he reluctantly went ahead with my suggestion. Just as I suspected there were some slight scratches on a few of the bearings but my mechanic said it's best to change them all. By the way I'm curious are there 6 sets or 3 sets. After successfully doing this I noticed that the noise has gotten considerably more quiet but I can still hear a slight noise. Should I change the knock sensor or did my mechanic's failure to lightly sand down the crank shaft which I suggested cause this noise to still be present? Besides replacing the motor which by the way only has 93,000 miles on it (Quite good for the age) what else can be done to remove this knocking. I cannot afford a new engine at the moment and all the used ones I found has double the mileage or higher like 400,000. What should I do? Suggestions please. Thank you

 

[LEVY]

Welcome

You should've listened to your mechanic. If crankshaft is worn, there is nothing you could do other than taking it to a machine shop.

At this time, a good engine with 300,000 + miles is better than your low mileage engine, so forget about your low mileage engine.
Replacing the knock sensor will not help, not at all, your mechanic probably already told you but you still wanted to prove him wrong.

And no, you were not right insisting your mechanic to drop the pan and replacing rod bearings, he was right from the beginning, you still need a new engine.

Sorry, we are here to help, at the end of the day, you'll still need a new engine, all the money you are spending trying to avoid a new engine will be lost forever.

Good luck.

 

[marvinstockman]

First, if you live in a warm climate, you can try a 20W50 oil.

Second, contact auto junk yards that will sell you a good used engine, and some of them work with local installers to guarantee both the installation and the engine.

Finally, who did you buy van from, and why did you buy it with a knock?

 

[LEVY]

Welcome

You should've listened to your mechanic. If crankshaft is worn, there is nothing you could do other than taking it to a machine shop.

At this time, a good engine with 300,000 + miles is better than your low mileage engine, so forget about your low mileage engine.
Replacing the knock sensor will not help, not at all, your mechanic probably already told you but you still wanted to prove him wrong.

And no, you were not right insisting your mechanic to drop the pan and replacing rod bearings, he was right from the beginning, you still need a new engine.

Sorry, we are here to help, at the end of the day, you'll still need a new engine, all the money you are spending trying to avoid a new engine will be lost forever.

Good luck.

Welcome

You should've listened to your mechanic. If crankshaft is worn, there is nothing you could do other than taking it to a machine shop.

At this time, a good engine with 300,000 + miles is better than your low mileage engine, so forget about your low mileage engine.
Replacing the knock sensor will not help, not at all, your mechanic probably already told you but you still wanted to prove him wrong.

And no, you were not right insisting your mechanic to drop the pan and replacing rod bearings, he was right from the beginning, you still need a new engine.

Sorry, we are here to help, at the end of the day, you'll still need a new engine, all the money you are spending trying to avoid a new engine will be lost forever.

Good luck.

 

[Baron]

the knock sensor doesn't detect rod knock from worn bearings, it detects knock from premature ignition of the fuel in the cylinder

replacing it won't make the knocking stop, you either need a new engine or to have the bottom end of your engine rebuilt

like levy said, a high mileage engine in good condition is better than a low mileage engine with problems

given the condition of the van and it's miles i'd say it's worth it for you to have it rebuilt/replaced

 

[Jeepman]

Go to a Mechanic that knows Chrysler engines. Those engines can be noisy anyway, especially at startup, per: https://www.aa1car.com/library/engine_noise_minivan.htm

The fact that it quiets down after startup (oil is flowing) is significant and likely nothing to worry about? All the STP stuff did was make the oil thicker. You can try a 5W-30 or 5W-40 oil (good brand name like Valvoline, no house brands). Are you in a warm or cold climate?

The 3.8L engine tends to use oil, sometimes quite a bit of oil, and still work fine. Is yours using oil?