Strange noise while driving...

[ant the ninja1]

Hey all, I had another account on here but for some reason I couldn't post things, it kept telling me it was locked out or something, anyway. I have a 02 Explorer XLT. Last year I had the transmission completely re-built and everything has been smooth. Recently though every time it shifts (or at least when I think it does) Ive been hearing a very odd noise. Its almost like a chain dragging across pavement but it doesn't do it all the time. Mostly when there is stress on the car like uphill or fast take off. Its usually quick but when im going uphill it stays there until it shifts. so I took it to the tranny guy and he put it on a lift and couldn't re-create the sound but when he drove it he would hear it. He also said the tranny is shifting beautifully. I had my bearings done yesterday because I thought it was that. Now that hum from the bearings is gone but that chain sound is still there.

I just looked this up on youtube and this is pretty identical with what it sounds like, just doesn't last that long at all and it doesn't do it when revving. Could it be my exaust?

http://www.youtube.com/watch?v=UvviBzphthQ&feature=related

 

[ant the ninja1]

No one? Ive been searching for hours and I come up with a lot of different things but no answers. One guy put it "When I accelerate and it shifts gears it sounds like change inside a metal can" That is exactly how it sounds on mine.

 

[01EXP5.0]

Probably not the exhaust if it doesn't do it while revving. Could be a heat sheild vibrating there are several heat shields under my 01 not sure about 02 and up. My thinking for the when and why it's doing it is harmonics of the engine, each gear has a sort of hum and vibration to the engine when this vibration changes at gear shifts could be throwing the harmonic vibration of the heat shield and causing the rattle. The trans shop probably used a two post lift and allowed the suspension to drop changing the circumstances that cause the rattle. My suggestion is climb under your X and look at all the heat shields for any possible contact points and tighten all the bolts. And this will work best if you can get under it without jacking it up. The plus side to all this is if it doesn't fix the problem then that's one possibility eliminated without spending any money. Please let me know if this helps. Thanks

 

[ant the ninja1]

So i just climbed under and banged around and I heard a rattle from somewhere but Im not exactly sure what its coming from. To be honest I dont know where any of my heat-shields are or what they even look like and its pretty hard to fit under the x without jacking it up. but I banged around and found a rattle from right under the passenger front door. so if theres a heat-shield there maybe thats it? I have no clue. I turned the car on and put the ebrake on and threw it into neutral and revved it to like 1500 and I am now hearing this constant knocking noise its not very loud but you can hear it if your standing outside the car. It does it idling as well. Not sure if this could have anything to do with it.

 

[charli]

The video on one of the previous post's is correct. Heat shields make this noise and also the cat can rattle inside and may be very hard to diagnose. Take a stethoscope and put it on the cat or pipe and you will hear where it originates from.

 

[ant the ninja1]

Ive gotta try the stethoscope thing but now that I have been paying more and more attention to it, everything single time, without fail it does it at 2500rpms. Even if it shifts or sits at 2400rpms it wont do it, soon as it hits 2500 it does. If it is just a heatshield, that just needs to be tightened right? No biggy there? What if its my cat?

 

[petejen]

98xlt,if i accelerate to quickly i get a loud bang,and if i go up a slite grade it starts to bang again HELP

 

[BigRondo]

98xlt,if i accelerate to quickly i get a loud bang,and if i go up a slite grade it starts to bang again HELP

Welcome aboard mate!

Try posting your question in the Stock 1995 - 2001 Explorers Section.

This is the Stock 2002 - 2005 Explorers Section.

Good luck with the fix! :biggthump