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My 98 540 IA has a rumbling noise at low speeds under 20mph.
It sounds like loud tires but it is not. When I open the door I hear the tires and its a different sound. Its not the brakes cause it does with no brake pressure and it does it when the car is off (coasting).

:driving On the highway its fine. Could it be rear bearings, diff, trans? :cry

What would make a louder noise at 10-20mph than at above 30mph. (excluding the increased ambient noise from the increase of speed)

It almost seems to go away when you go faster.

Anyone experience this problem?

Thanks

:banghead
 

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Originally posted by lbriedis@Sep 4 2003, 10:42 AM
Could it be rear bearings, diff, trans? :cry

Those were my first thoughts. I dunno :confused
 

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cats maybe?
 

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I had Toyo tires before I changed all 4 to Yokohama AVS ES100's.
The Toyos were noisy and were like you said, "rumbling" at low speeds, esp. 20 to 30 mph. Didn't hear them at high speeds. At first I thought they were wheel bearings or rotors, Then everyone told me Toyos sucks!!!

Don't tell me you have Toyos! :lmao2
 

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Oh...and tires can sound different from outside and inside the car. Inside the car you hear the "sound effects" thru the wheel wells/arches whereas outside, the sound is dispersed into the open together with the wind etc.

Good Luck! Whatever it is...
 

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I have a similar issue with my 2000 540i/6. I used to keep the car at the cottage, but now since I put my Z/06 away (insurance got too high), I am driving the 540i for the first time in the city on paved roads. It has a noise not unlike noisy tires, and it does go away at speed.

Maybe I'll try to record the sound and attach the sound file. Anyone want to compare to try to figure out what the noise is?
 

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Originally posted by BeelZibub@Aug 11 2004, 09:30 AM
Try running it without tyres and see if it's quieter - if not put them back on.
Genius... :clap2

I have Dunlop SP Sport tires on the car. The noise is in fact tire noise. Sounds different inside than from the outside (not just quieter, but it has some resonance).

My friend put Kumo MX's on his 530i and has a similar noise that he did not have with the Michelins he had on the car prior.

I'm looking for some bigger rims to put on the car anyways, so I'm not going to change out the rubber just yet.
 

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Only joking

I run Dunlop SP SPORT 01 rear and sp sport 2000 front on mine and they aren't the quietest of tyre, they stick to the road like shit though. I have been told continental economy tyres are very quiet (and save you money) but don't grip half as well in the dry although are better in the wet - I haven't tried these though, just what I 've been told.

I, also was hoping my tyres would last until I can afford new rims but I ve spent the last 3 months enjoying being able to get the back end out on bends so the rears are now shagged and I have a nail in the front n/s - so I guess it'll be an expensive weekend and the AC Schnitzer 18"'s will have to wait another 6 months.
 

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I had similar problem on my 528I, I did change 2 rear bearings she is very quite now. Also I had the OEM 17" rims on it, replaced them with the original 15" rims and tires no problems whatsoever. I sacrificed the look for what comes original on the car. remember 17" and 235/45/17 tires are too much of a load on these bearing. technically This makes sense to me for the look of it? I am not sure.
 

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Originally posted by BeelZibub@Aug 16 2004, 03:30 AM
Not quite sure why 235/45/17 would increase load on the bearings - they are the same rolling size as the stock 15"'s.
Probably for the same reason a larger rim will decrease your acceleration and ability to brake - they both are not nearly as strong with larger / heavier wheels.

a 17" wheel is also USUALLY quite a bit heavier than a 15.

everything has a consequence :(
 

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So BMW gave the option of 17" rims knowing full well the cars rear bearings couldn't handle the tiny change in weight - Oh no I'll never carry a passenger again or do my shopping in my beamer in case the extra weight buggers it up!
 

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I don'y think the issue is with the weight (like in pounds of passengers or the weight of the 17" rims VS. the 15" .As you know the 17" comes with 235/45/17 tires. What kills the rear bearing and gives you the rumbling sounds is that number of 45 above. more or less the width of the tire that contacts the ground.
Also what gives you those bubles on the outer/inner side wall of the tire is the other number of 235 (low profile) whenever you hit a bump on the road it is most likely the rim hitting the low profile rubber. even if you are very carefull driver.

Now lets do some high school physics: I have two types of tires on a 528I one is 215/70/15 continental which is standard on the E39 and 235/45/17 Michelin as a sport package (never again though) which tire you think has MORE SURFACE AREA? is it the wide 45 or the narrow 70? you guessed it . With that kind of surface area on the 45 tires you talking some serious friction between the rubber and dry pavement; which in turn translates into extra work for the bearings. You simply need more power to turn that wheel.

Slippery when wet? Thats right in addition to kissing goodbuy my traction in winter (again MORE SURFACE AREA slipping on ice. I couldn't make it out of my driveway with the 45s in winter. I don't have that problem anyomore with the 15" so much for surface area.

regards
 

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Right now for some common sense

The 70 or 45 bit you're talking about (Sidewall height NOT width) is actually a percentage of the WIDTH (215,235) of tyre ie 70% of 215 gives you a 150.5mm high sidewall as 40% of 235 gives you a 94mm sidewall.

Also the "Standard" e39 size you mention is ONE of Several "Standard" sizes on e39 - mine came as "standard" with 225(WIDTH)/60(SIDEWALL HEIGHT/PROFILE)/15 (RIM HEIGHT) Others came with 16" and even 17" rims. I again ask you , did BMW add these rims knowing full well that they would cause damage to the bearings of the car???

I can't quite figure out what the rest of your post is saying - Again I repeat, as long as you use a correct size when adding larger rims (all correct & compatible sizes are listed on a sticker inside the drivers door area) you have the same rolling size wheel (ie the wheel & tyre stand the same height), therefore it should not effect performance.

Width = added friction??? stand one of each of your wheels next to each other and roll them gently with each hand, do you notice any difference? added friction only means the wheel is sticking to the road not slipping on the road when forward or sideways forces are applied - which would you prefere?.
 

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PS

Most heavy cars with a lot of power/torque are susceptable to rear bearing rumble - this is due solely to the weight versus torque. When you hit the throttle hard the whole of the drive train receives a sudden jolt of power the higher the torque or the higher the weight the bigger this jolt will be - as the wheel bearing is the weakest link within the drive train (if the tyres are doing their job and transmitting the power onto the road) this jolt can cause them to fail over time. The big Jaguars have suffered with this problem for years sometimes requiring bearing changes every 12000 miles (depending on how they are driven).
 

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Beelzibub

Excellent common sense, you thoughts are very stimulating I will add a reply to you very soon.
regards Bill
 

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Bill

I've done a little research for you (although I already knew most of this due to the fact I used to work as a mould operator at a tyre manufacturing plant), try the following link I'm sure you'll be thrilled by the simple explanation of tyre sizes coupled with as much high school physics (proper physics not guesses) as you can shake a stick at - and not one mention of bearing over load from fitting wide tyres (in fact as hard as I try I cannot find a single site on the whole www to substantiate this).

www.chris-longhurst.com/carbibles/index.html?menu.html&tyre_bible.html

regs'
beelzibub
 

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Dear Beelzibub
Thanks for the insight I will explore it further also please feel free to check my post dated 8/17 titled "power steering fluid mixed with rough idling" on 97 528i , any insight is greatley appreciated as usual; talk to you soon
bill
 
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