Annoying Vibration at 1500 RPM

[Mad Miff]

Hello LC people, I have had my 2005 J120 3Ltr diesel LC5 since August and I love everything about it apart from one thing. As I drive and reach 1500rpm, regardless of speed, I can hear a vibration/rattle noise coming from the front right but because it only happens while it's in gear and moving, it's very difficult to find.

I have tried various things but with no success so far, it sounds like a plastic panel is knocking against something else or visa versa and it is really annoying and spoiling what is in every other way a perfect car.

I wonder if anyone else is having this issue and managed to locate the cause of the noise.

Thank you.

 

[Mad Miff]

Update, been messing around trying to resolve the rattle noise, seems it is more noticeable when facing up a hill but I still can't put my finger on what it is.

 

[Shayne]

Check the fan isn't hitting the cowl .

 

[Mad Miff]

Thank you, I have thought of that but it doesn't appear to be and the rattle is more like something tapping against something which is hollow in order to create the resonating as opposed to a rotational sound if you see what I mean. Biggest problem in finding it is that the car has to be in gear at 1500 rpm but I don't know of way to maintain those revs without the auto box changing up.

 

[Shayne]

I don't have a 120 and i could be way off the mark but i am wondering if the intake comes from the drivers side wing and if so is there is a sort of catch pit inside the wing to stop leaves and such reaching the airbox ? maybe someone with more knowledge can say if its possible a stone could find its way into there ?

 

[Mad Miff]

The air intakes come from the front grill and travel through ducting in the bonnet. It seems to be too consistent at those revs to be a stone.

 

[clivehorridge]

Not much to go on with this, and I know nothing of 120s either, but it could be a CV or a UJ.

Not it clear whether it's 1500 rpm in any gear, but it's worth having them checked out, the sound they make can vary a lot from truck to truck.

 

[Deleted member 13129]

HI
The air intake you mention is for cooling the intercooler. The air intake to the engine is through the driver side wing to the air filter. My car is a 2009 lc120 invincible 69k miles
it has a strange noise at arould 1500rpm and also sounds like there is an owl under the bonnet up to 2000rpm but it runs great so i have stoped worrying about it as its my first diesel. I have allways had V6 and V8 petrol engine cars in the past. I have read in other forums same story about the noise.The intake just before the filter box could have a propeler to direct bugs leafs stones away from the filter powered by air sucktion as in some cars.I have only had the car since this july but i love it to bits.I keep doing little mods to it and allways keep thinking what mod to do next.I would not worry about the noise just enjoy being the owner of such a great car

 

[Mad Miff]

Thank you for your advice, you are right now I think about it, the engine air intake does go through the right inner wing. One mod I just did today which is fantastic is to stick real leather over the silver centre dash trim either side of the clock to stop it reflecting in the windscreen.

 

[GeekOKent]

Its pretty irritating. My lc5 does it too. As do quite a large number of these trucks. it is the airboz in my case. A bit of rubber under the housing cures it for a few months then i either need to move the rubber. The most absurd thing is that the little piece of plastic on the bottom right of the windscreen on te outside picks up on the vibs and reasonates in SHM with it. Just removing that plastic drops the 'intensity ' of the sound heard by the driver. But the real fix in my case has been to wedge the airbox in better.

 

[Rob Cowell]

Its pretty irritating. My lc5 does it too. As do quite a large number of these trucks. it is the airboz in my case. A bit of rubber under the housing cures it for a few months then i either need to move the rubber. The most absurd thing is that the little piece of plastic on the bottom right of the windscreen on te outside picks up on the vibs and reasonates in SHM with it. Just removing that plastic drops the 'intensity ' of the sound heard by the driver. But the real fix in my case has been to wedge the airbox in better.

I think a genuine filter resolves this. When I bought mine all was good. I changed the air filter the first time I serviced it and had exactly this problem and used the same solution. Although fortunately mine seems more permanent, 60K miles later. Be interested to know if anyone gets this with a genuine filter, although no idea what they cost.

 

[Shayne]

I think a genuine filter resolves this. When I bought mine all was good. I changed the air filter the first time I serviced it and had exactly this problem and used the same solution. Although fortunately mine seems more permanent, 60K miles later. Be interested to know if anyone gets this with a genuine filter, although no idea what they cost.

The filter itself is rattling I grease the rubber seal on my air box lid to ensure everything must pass through a K&N filter if that's any help .

 

[Simon5030]

Well whatever is causing that rattle on your cars must have fell off on mine as i have no rattles at all (except wehn cold for the first 5 mins)
I have only had genuine filter £25 including drain plug seal

 

[GeekOKent]

I have a genuine filter sitting at home. Will swap it out and report back.

 

[Mad Miff]

I spent a few hours driving round and round but still can't pinpoint that bloody vibration yet. I have another question though, is the power mirror control switch meant to illuminate?

 

[GeekOKent]

Swaping the filter made no diff to mine. Have you reseated the corner plastic at the bottom left ( when looking at truck from the front ) ?

Mirror control switch does not illuminate on my truck either.

 

[Mad Miff]

I will look in the light tomoz, cant believe those switches aren't illuminated, it has to something very simply but so hard to locate cause it only happens when the car is moving, you cant just rev the engine to hear it.

 

[silvercruiser]

Well now im a 120 owner i can also report that i too have the noise. and yes its bugging me already so if it doesnt rain to hard tomorrow il be searching for this noise.

 

[silvercruiser]

Its pretty irritating. My lc5 does it too. As do quite a large number of these trucks. it is the airboz in my case. A bit of rubber under the housing cures it for a few months then i either need to move the rubber. The most absurd thing is that the little piece of plastic on the bottom right of the windscreen on te outside picks up on the vibs and reasonates in SHM with it. Just removing that plastic drops the 'intensity ' of the sound heard by the driver. But the real fix in my case has been to wedge the airbox in better.

il start my investigations/fixes Here.

 

[Mad Miff]

Ok I found that the vibration only occures while the car is in gear at 1500 revs. So even if while moving I push stick to neutral and rev engine to 1500 there is no noise, pop it back in gear and it is back straight away at 1500 revs.

So in the morning I am taking it to a Mansfield 4x4 so they can lift the whole car and run it in gear while listening outside for the vibration, if they cure it not only will it be worth the money as I don't have the equipment to lift the whole car, I will be able to report back what was causing it.