10 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHShould a C4 be more noisy than a C2
Reported repair
Replace tires
Reported resolution
1
Reported fixes
0
Unsuccessful attempts
1
Discussions
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Reported fix
Replaced tires with SO2's, howled too much so dealer took off and put on Toyo. No more noise, but car is unstable.
Leading evidence: 'Replace tires' (1 discussions report resolution; 0 report an unsuccessful attempt). Across 1 matching discussions, the most frequently mentioned possible cause is 'culprit' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Replace tires' (1 discussions). For that action, 1 discussions report a resolution and 0 report an unsuccessful attempt. The most frequently reported fix is 'Replace tires', supported by resolution reports in 1 discussions. These are forum reports and suggestions, not a confirmed diagnosis.
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Performed · outcome unconfirmed
BTW - I did have the car checked for wheel bearing, but that was not the howling issue.
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When I replaced the fronts the noise went away, now that the rears are down to about 25% they are getting noisy again.
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Performed · outcome unconfirmed
I am running the Conti's, good for wear, but they are noisy.
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Discussions that suspect a cause
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10 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
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I have a 99 model C4 tiptronic. I find that it makes a howling noise (almost like a failed bearing) from the front-between 40 and 75 mph. It goes above 80 (or gets drowned out by the appalling roadnoise-not sure which).
My question is- does having 4 wheel drive and a diff at the front make the car inherently more noisy or is there a fault with the car. I even suspect that it could be the Bridgestone SO 2s but am finding it difficult to swap the wheels out to check.
I have an 01 C4 with a 6 speed and no howling noise, other than when my tires start to wear out and then the howling is more like a roaring and it comes from the rear. I would get it checked out.
Regards,
Mike
C4 tip cab here ('00). The howling noise seems to come from worn tires. The more worn, the louder the noise. I am running the Conti's, good for wear, but they are noisy. first time I replaced the rears the howling went away, as the fronts wore out the noise cam back. When I replaced the fronts the noise went away, now that the rears are down to about 25% they are getting noisy again. At the moment the harmonic is between 78 and 84 mph. As they wear more, the range gets wider. I am going to change tire brand next time so I am following the tire threads closely.
C4's tend to "pick up" more tire noise - there is a school of thought that says it's the AWD system - light vibrations and sounds may be amplified by the drivetrain layout. I don't know if that's true, but I've heard it from several sources. The "fix" is to use the quietest tire - not the Conti's!
J
Went from a 99 C2 Coupe with 17" wheels to an 02 C4 Cab with 18" wheels. A little more road nosie, but no howling. I think most of the difference is due to the different wheel size. But I wouldn't call it "appalling" compared to the C2, so I would first try to eliminate your tires as the suspect.
Regarding quite tires, I had the Conti's on my car originally. Yes, noisy. Then, for a brief howling moment, I had S02's. Man, were they loud. I tried the S03's and they're quiet independent of tread wear. I have C4 Cab so I hear it all. I love the S03's, even though my P-car dealer wouldn't install them because they weren't N-rated. :-(
01 C4 here, noisy howling too. Replaced tires with SO2's, howled too much so dealer took off and put on Toyo. No more noise, but car is unstable. We're still trying to get the pressures set to get rid of the odd feeling and handling. 36front, 40 rear makes the car feel better but rear is not glued in corners. Setting rear to 42 makes the instability come back. Odd. Time to take it into the highend tire and alignment shop this week.
BTW - I did have the car checked for wheel bearing, but that was not the howling issue. The S02's were not matched and caused the issue.
I agree with Gretch and others. It's the tires. I think if it were more a mechanical thing you would get some "whine" with the top up. I don't. Just get it with the top down (in addition to the wind, of course), but with top down and windows/windscreen up I don't hear the whine either. Therefore...tires are probably the culprit.
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