The past few weeks I've been hearing what I think is that familiar sound of a bad rod bearing. A nice series of knocks from the motor for about second on cold starts, and then the steady quiet knocking at idle. My Jeep now sounds like my old Ford did, ha! Anyone have similar problems? Maybe I got a dud? Only 28k miles on the ticker, I drive like an old lady and have a light right foot off road.

I run Mobil 1 Synthetic 5W-20 with Fram filters, fresh juice every 5-7k ... I woulda bought the cheap oil if this was the end result.

Aye, anyways, time to schedule a visit at the local dealership.

-matt

 

You might of got one of those Friday after noon or Monday morning motors.

 

ROd bearings ave VERY easy to diagnose. While it's running, remove each plug wire one at a time, and put it back. When you get to the cylinder that's making noise, it will quit because you just removed the load.

 

Absolutely correct....X2

 

oh hell i would not touch the plug wires for anything when its running due to one time, bad wires - leaning over - no shirt shoes - rain =

 

YOU NEED A NEW OIL FILTER!!!!!!!!!!!


I had the same problem after my first oil change. Knock on cold start.

Some oil filters have a weak anit-drainback valve (very inportant on a side mount filter). It lets all the oil drain out of the filter when the engine is turned off.

I tried a few diferent filters and this is the only filter I will use.
Motorcraft FL-910. I saw a thread on here about this very subject and took somebodys advice.

Use the Motorcraft FL-910. Walmart, Just over 3 bucks.

It will fix your cold start knock.

 

Well said.

 

Yeah, start with the oil filter and go from there, but I see you are using the Fram which according to people's first-hand experience on here seems to have a good anti-drainback valve. Cheap enough to try first though. If you are hearing it beyond initial start-up then you may have a bigger issue though.

 

If you overheat your engine it will due the same thing.