C5 Tourer Road Noise

[Mike O.]

Yes Paul,

 

Our roads are usually covered with the dreaded coarse chip bitumen.

I have always thought it was caused by the hot summers, but recently discovered,

that even Sweden is going in this idiotic direction...

 

Anyway, I have now picked up the car and love it. What a superb ride comfort on 17s pumped to a rather low pressure.

40 psi front, 35 psi rear according to my pressure meter. My son's meter showed 34 front, 28 rear. Lovely accuracy...  
 

On a smooth surface the car is quiet enough, but on a typical freeway it is far from it, so watch this space in a few weeks... 

 

Cheers,

 

Mike O.

[Mike O.]

First stage done.

I covered the floor starting at the vertical mini wall under the tailgate and finishing at the base of the vertical wall under the rear bench seat. 

Haven't managed to test the results on a really bad surface yet, but it is already obvious that the road noise level has dropped significantly. The noise has subjectively moved to the front of the car, as it did in my previous cars.

Next stage: the wheel arches. 

This will balance things out a bit, but will make engine noise more noticeable.

So, the third stage, engine bay, will need to happen. 

I am doing a 3-day country run next week, this will be a great test of stage one effectiveness.

It will also enable me to test the bi-Xenon headlights on really dark roads.

At the moment I think they are not as good as my previous model's halogens with +90/+100 bulbs. 

[qman3428]

Interseting twist on the tyre noise issue. My new shape exclusive saloon did not have the noise, until I changed the brake pads then the noise appeared. There is a lip of metal on the outer edge of the disk caused by brake wear, I ground it off the offending wheel and the noise was massively reduced. Next week I intend to to the other three wheels (weather permitting)and will report if it makes the noise go away completely. I will also be changing tyres that week as my goodyears on the rear have had it. Might try continetals next they claim to be 2db quieter.

It could of course be that I used non OEM brake pads and the pad material could be the suspect but I believe the pad vibrates in the groove causing the noise, by removing the groove the pad has nothing to vibrate against.

[Mike O.]

The bi-Xenons were aiming too low. After adjustment, on straight roads they are good, but not spectacular.They are fantastic on really twisty mountain passes full of hairpin turns.

The noise deadening stage one worked, but was not near enough. So quiet on a smooth road, still so noisy on coarse chip.

Michelin Primacy HP tyres have obviously not been designed for such noisy road surfaces, nor has the rest of the car.

Stage two (wheel arches) will most likely happen this Easter long weekend. I have already bought the second bulk pack of Dynamat Extreme.

[Mike O.]

Stage three almost finished. Wheel arches are covered with Dynamat Extreme - both the arches themselves and their linings.

Again, a significant improvement. I will finish stage three and then do the engine bay.

 

BTW, the engine noise has somehow NOT become more intrusive with the rest of the car being quieter.

When all is done, I will drive my car with another Tourer back to back to test the effectiveness of my efforts.

My expectations are on a high side... 

 

Regards,

 

Mike O.

[Stylo]

Hi Mike, You are the person that open my eyes for that in Australia there is Citroen cars available!  


Very interesting posts i keep watching the situation because i am looking for C5 2010+ .. :)  I will be happy to read what happened after stage 3+ Dynamit... 

[Mike O.]

Hi Stylo,

 

I got my stage numbering wrong.

Stage 1: Back of the car inside - done, nice improvement.

Stage 2: Wheel arches - 80% done, again noticeable improvement.

Stage 3: Engine bay - not done yet and will probably need to wait till October.

I will report the progress. 

 

I still love the car. My fishing buddy is a Toyota ((Prado) man, but even he admitted, that the new C5 has easy access to everything in the engine bay. His jaw recently dropped, when I was getting the boat out of the lake, going up a steep slope without a trace of any wheel spin (the magic of the Snow mode).

 

One more thing: with cars like the C5 it is extremely important to have a good dealer.

I don't let anyone except myself and Continental Cars in Padstow touch my Citroen(s).

 

Mike O.

[derekn]

I have a mk 3 tourer on 19 inch wheels and recently changed front tyres for very expensive Michelins. Road noise was unbearable so have since changed tyres again but with very little improvement. In desperation car has been to my local specialist who agrees something is not right but can't find anything wrong. He even changed front wheel bearing as a precaution although the original was found to be fine. 

 

Has anybody found the cause or a cure please?

[Mike O.]

Where are you located Derek? 

In the coarse-chip-bitumen crazy Australia?

 

Having said that, I have recently noticed that quite a few roads in/around Sydney have now been covered with a much quieter bitumen mix.

So much so, that I still have not done Stage 3 - the car is basically quiet enough now, even on more than half-worn 17" Michelin Primacy HP tyres.

In a year or so they will be changed to Toyo Teo Plus, which will further reduce the decibels inside the car.

 

So, the cure consists of:

1. Changing the wheels to 17" (I don't think 16" wheels on Mk3 would be legal in down under).

2. Having quiet tyres on them.

3. Noise deadening the car body itself.

 

See my previous posts.

 

Cheers,

 

Mike O.

[derekn]

Thanks for your comments Mike; I'm in Yorkshire UK, and yes, the noise is very much dependant on road surface, but there is clearly a fundamental issue for the inevitable road noise to be transmitted into the car so badly. My latest tyres are alleged to be among the quietest available but I guess the issue is not helped by my 19 inch wheels. Not sure if I can justify replacing all wheels and tyres in the hope that this might resolve the problem though.

 

Incidentally been in touch with Citroen UK who suggested I go to my local dealer. Not really the answer I was looking for!!

 

Cheers, Derek

[Mike O.]

Derek,

 

Have you compared your car to a brand new one of the same (more or less) spec?

I would do a test drive on the roads you know to be noisy to have an idea...

And immediately after I would drive your car on the same roads - this will tell you if it is your car or just a C5 design fault.

 

What possessed you to buy it with 19" wheels?

I remember reading a British test report, where the tester said he felt sorry for Citroen engineers, whose fine efforts were ruined by the marketing guys putting big wheels with low profile tyres on the C5.  

 

Are you sure the air pressure in your tyres is not too high? Be careful, yours are low profile tyres and as such very prone to damage on bad roads, so you can't go very low...

 

Don't be afraid of Dynamat - it is so easy to apply in reasonable temperatures (it becomes more pliable as the temperature rises - not a problem in Sydney) and it does make a difference.

 

Cheers,

 

Mike O.

[derekn]

Hi Mike and thanks for the comments

 

I haven't compared to new, no but the noise is far more noticeable than on any other car I've owned. I have to conclude that it must be an inherent fault that is exaggerated with 19 inch wheels. Incidentally the car was fitted with these when I bought it as the previous owner who bought the car new must have specced them although standard fitment on my car is 18 inch anyway.

 

Air pressures are fine thanks.

 

My rear tyres will need to be replaced soon so I'm researching a super quiet tyre which I can then swap onto the fronts in due course.

 

Strange that if it is just road noise then why is there no appreciable noise from the rear?? It has to be to do with noise transmission through the front drive train/steering/suspension somewhere. Such a shame because the car is so quiet otherwise.

 

Cheers, Derek 

[Mike O.]

Hi Derek,

 

No noise at the back, hmm...

Maybe the previous owner noise deadened the rear?

That is the first thing I did when I got the car - the noise was coming predominantly from the rear.

 

Are all the rubber elements in the front suspension OK? I am not sure how many there are, but they certainly isolate the body from the moving suspension elements.
 

I frequently am a passenger in a Toyota Land Cruiser Prado. It has a frame isolated from the body by some elastic compound - now that is a solution for crappy road surfaces.

Ride comfort on my friend's over pumped tyres (he has done 130,000km on them and will still do a few more) is not quite to C5 standard, but the silence....

 

Cheers,

 

Mike O. 

[Manthony.h]

Hi All,

 

I have an early Mk111 C5 on 18" wheels with hydraulic suspension and can confirm that there is no tyre roar from the back, only the front.
I have tried different makes of tyres and some are quieter than others but not that much difference. At present I have Goodyear Efficient Grip fitted which are quieter than the Michelins.

I get a roaring noise on gravel dressed surfaces and a "thrumming" noise on smoother tarmacked surfaces similar to worn wheel bearings (these and the drive train have all  been checked and are fine)

I would be interested to know if the steel sprung cars are as noisy as the hydraulic ones?

 

Regards

 

Martin

[derekn]

Interesting point Martin; Does anybody else know?? You describe a 'thrumming' noise which is very accurate, it does indeed sound as if a wheel bearing is on its way out although on my car the noise starts from as low as 20mph and then remains at the same level regardless of speed, which is not consistent with a wheel bearing. Anyway it can't be my wheel bearing, since I've just had it changed, even though when removed the original was absolutely fine.

 

Oh well!!

 

Cheers, Derek

[Mike O.]

I am starting to think, that Citroen people have been changing some suspension elements from one year model to another without telling anyone.

Just like they have been doing with acoustic side windows or interior equipment levels.

 

Cheers,

 

Mike O. 

[paul.h]

You could look at the parts diagrams and see if the part numbers have changed on newer cars.

[durbis]

Just got a 2013 tourer and it's noticeably noisier in the tyre department than my old C5 (2004 saloon). I found on the saloon tyre noise could be very greatly reduced - to the point you didn't need to turn the radio up on rough roads - with Pirelli P7 tyres, which also gave far better wet weather performance than the Michelins. The new tourer has different tyres front and rear (neither particularly good makes), so will be changed as soon as my wallet recovers from buying the car. I'll let you all know how P7s do on this one.