Hey guys. I've had my Ram for 2 years now and its never given me any issues until lately. Its an 04 with the 5.7 Hemi.. 96k miles.

Every so often when I start it (I always let the fuel pump prime before turning the ignition) it'll have a knock. It'll go up with the starting revs and go for about 5 seconds and fade off. Sometimes it won't go away so i'll turn off the truck and restart. Sometimes it won't even do it a second time.

I've done the oil changes religiously since I bought it. Just replaced the spark plugs this sunday. I was hoping that the knock was coming from a slight misfire due to old plugs. Still does it.

Oil pressure always goes up to normal and sits dead middle. Never fluctuates. Oil is fresh, about 1000 miles on it so far. Oil is at the top of the hash marks. I only run the Dodge recommended 89 octane fuel.

I'm not sure what else the problem could be. The engine doesn't drip a single drop of oil and when it runs it runs beautifully. I'm hoping that someone might be able to shed some light onto it for me.

 

Are you sure it's engine knock and not just the intake manifold tapping? Very common for the bolts to shear at the heads. Will increase and decrease by engine rims and usually softens to sometimes inperceptible levels after engine heat swells the gasket.

Look at the rear most (closest to cab) bolts as they are usually first to shear...

 

Definitely sounds louder than that. Usually happens during the warmer parts of the day. I'm pretty sure that Dodge recommends 5w30? I'm running 5w30 high mileage.

I'll try to get a recording of the sound its making but its definitely worrying. Oh and its much louder than the subtle Hemi tick.

 

I dunno, I've heard them manifolds slap loud enough the owners thought they threw a rod from a couple of sheared bolts...

 

Well i'll definitely be checking that this weekend. Thanks!

When I had just finished installing my new spark plugs on Sunday, I fired it up. It sounded weird at first and my roommate had said that air shot out of the passenger side near the back. I'm hoping that'll be a hint.

Now would it be better to just retorque the intake manifold bolts or replacing them all together? Gonna have to print out the page from the manual too.

 

You can't re torque a bolt that has the head sheared off. That's the issue people are having, vibration is actually shearing the heads off the cheap bolts. Gonna be fun extracting the bolt out if that's the issue. Been there done that, although they are a lot easier to get at on a Hemi as opposed to a 4.7 V8...

 

You may have some carbon buildup on the pistons