have had my 5.5 for almost 10 years 114k miles. Engine rattle began at 40k. Got the short block replaced at 40k under warranty. Only Mobil 1 snythethic 5w 30. Around 80k the rattle began to show up in every gear I drove in. I have read all threads and know the possible reasons: bad rings, oil consumption, bad gas ( 91 only), dirty or leaking oil in Front and rear valve all replaced and done and any other minor issues that arose. i think its the cheap rings that the engine has in the pistons.

My only question is should I be worried that the rattle will eventually crap out my engine or since I am at 114k that if nothing has happen by now besides the sound, just let it be?

 

When I first seen the thread title, I was thinking it was going to be the rattle on start-up from the timing chain. But seeing that u said in between shift n such it just doesn't sound like an engine internal problem. Unless it was a risk pin on the connector rods. But are you sure you looked at all other possibilities. Exhaust rattle maybe? Even the hood of the car could make a rattling noise. Their are two rubber grommets on the hood that u could turn to take up slack in the hood. Heat shields are a possibility also. Have you visually checked your engine mounts??? I'm not sure if your car is a auto or a 6spd, hopefully u are a manual. But I noticed that rattling noises are more noticeable if u have the car in reverse with the emergency brake pulled up and have someone quickly engage the clutch almost to the point where it is about to cut out then disengage quickly...You will be able to see the movement of the engine and see if its moving too much. It also may enable u to reenact the rattle while stopped so that you can isolate the problem....I hope I helped you!

 

thanks for your input. Sorry I think I mislead you. The rattle comes in any gear( Manual 1-6 speed) when i am fully engaged in a gear and I acclerate at a moderate pace, the rattle appears and it is coming from the engine without a doubt. HeatShields, I guess I should look into that more. It would not be engine mounts that because I know how that sounds and its not that. Does the heat shields rattle or somethign when you accelarte. This does not come about when I am in neutral and press on the acclerator. IT does go away if I accelerate and floor it. It is only when i do a normal accleration on the car again in any gear 1st, 2nd majorly in 3rd and 4th and a little in 5th and 6th. I have tried it on the freeway and its so loud that I can still hear it even with freeway noise.

 

What octane gas are you using? When is the last time you used a fuel injector/combustion chamber cleaner? Sounds like pre-ignition, aka pinging. Had it in my 4AT at light throttle from 1500-2000 rpms and it was noticeably worse when I was in Phoenix where the premium is 91 octane and not 93 like it is here. As long as it isn't severe, it shouldn't be a problem. I had 194,595 miles on my 4AT when it was hit and totaled and it was running great. So far, I haven't noticed any pinging with my 6MT. It also doesn't use oil like my other 5.5 gen did though

 

At what RPM's are you noticing the rattling?
Do you have a CEL on, or at least intermittently on?
If so, what code is it?
If you can tell that the rattling is coming in around 1700-2000 rpm or close to that range in each gear, there are several threads on here.

Problem could be heat shield, the timing chain or bad cats. Try to find out if you can see if the rattle comes at a specific rpm each time and if so, do a search on those.

 

I would still recommend u attempt to put it on a lift and run it a little. But if its load dependent like your describing then it may not replicate the noise. Another thing to try would be letting someone else drive it around in a parking lot as slow as possible so that you could get a better ear on it(Should be able to isolate what part of the engine bay it is coming from...may even be under the car, headers or exhaust). Speaking of a better ear, have you gotten any opinions from other people that around u that can ride in the car? Dont be afraid to open the hood, pop off that engine cover and place a hand on parts that could be the culprit. Noise is nothing but vibration, so it would also be helpful to tap things with a screw driver or a small hammer....TAP is the key word on that. Another thing that comes to mind is that u mentioned it doesnt make the noise in Neutral....remember that the engine moves under load, therefore a component maybe touching something during acceleration that it may not touch at idle.

 

+1

 

I'm having the same issue too only at 3k rpm...

That and some ping (sounds like octane ping) through all the gears...

Ran 93 oct. since bought

 

i had a rattling issue with my car when i changed my oil i put a bottle of lucas and ever since i havent heard any rattling

 

sounds like two pie pans rubbing almost. I'm removing mine this week. And when I floor it its not present, but light load any gear starting off and at light throttle I get that noise