strange humming noise

[amiers]

have always had a bit of tyre/road noise in the Fairlane and recently had to replace the front wheel bearings. i do a lot of highway driving and the other day i didnt have the cd on flat out,as i do, and i drove for about 20 k's in silence. i noticed that the humming ,tyre noise?, goes away when i went over dips in the road!! as the suspension flattens the noise dies and when car is back up its back.

idea's please?

[JC]

Wind tray under the front of the car???

[ronwest]

It may be that the extra weight on the tyres causes the hum to change/disappear (tread pattern flattens).

[champ]

Me too! I've got this constant humming!!! Driving me insane. Have just put brand new Michelin tyres on, been told its not a bearing, but there is play in front calipers. Could this produce this noise? I've been driving fairlanes for over 20 years and have never had this! Any suggestions pls?

[revcore]

I had the same thing in my old EL Fairmont wagon...Turned out to be uneven wear in the front tyres.

[peterljohnson55]

Are you sure the humming is coming from the front lower? One side more than the other? I ask because the humming I had in front was the rear-view mirror on windscreen. It was a very slight loose fit to the bracket.

[champ]

Don't know... Have totally given up by now. Am due to go & get the calipers done in a couple of days, will see what they say about the humming noise. They told me it was tyres, which yes, admittely, it has lessened but it is STILL THERE!! Almost gave away my car for another 2 weeks ago because of this! So glad i didn't though.

[peterljohnson55]

I suggest you ask someone to drive it for you on a long, straight and uniform stretch, and at a uniform speed, while you sit in the other seats front and back, with your eyes shut to try and pinpoint the direction from which the noise is coming. Do it again using two other speeds. Also, try it on different road surfaces.

Take your time when you do this - will need some concentration too, and hopefully you will pinpoint the location problem.

[Maka]

What psi are you running in your tyres? Check your pressures on the off chance one is slightly deflated than the others. Worth a try & free!

cheers, Maka

[champ]

Thanks for the suggestions people. Tyres have 36 psi. They are 235/45/17 97w. Don't know....tonight on the way home it actually sounded like its coming from the back and it was actually louder with a slight vibration through the steering & the car actually felt like it was dragging.

[peterljohnson55]

Hmmmm . could be diff

[champ]

You think???

[peterljohnson55]

Yeah I do Champ, could also be wheel bearings ...
but, for your car, what do you think?

[champ]

Well.... guess what....hub/wheel bearings. One front & one rear. Booked it in to get them done next week. Yay! no more noise... But you are absoloutely right! No-one knows your car like you.... Tyre noise! What a load of crap!

[mik]

tyre noise can doit, and especially if one is getting ready to delaminate, don't ask me how i know that :(.

[champ]

Ummm stupid question but what is delaminates.

[mik]

Originally Posted by champ

Ummm stupid question but what is delaminates.

not a stupid question , the best description i can come up with is the tyre is made up of parts, the main part a large sheet of rubber moulded to shape that holds the air, these days most tyres have steel belt/s reinforcing , and the main tread area moulded over the top, in certain circumstances the main tread can come astray from the rest of the tyre, in some cases the steel belt will come away with the tread, or the other way around, lots of reasons for this, old age, abuse of the tyre, over heating ,lack of inflation, poor manufacturing, air getting between the layers due to a puncture repair and forcing them apart.
sometimes it will start with a slight bubble or deformation of the tyre, in the tread area, in the worst case scenario the tread can come off and the tyre blow, they don't always blow, sometimes they just lose bits of the tread/belt and stay inflated, i had one let go at 110 kph during an overtaking manoeuvre with about 4 foot of steel belt whipping around under the front guard(very exciting in a bad way).

[peterljohnson55]

Examples of delamination here
http://www.intechopen.com/source/htm...ia/image13.png
and here
http://www.d2au.com/index.php?topic=353.0

[champ]

Wow! I must admit ive been pretty lucky. Havent ever come close to anything like that. But then again im a bit of a princess with my car.....we are connected at the hip you see so for every little noise, off i go and get it sorted. Gotta love a quiet cushy fairlane.....hehe

[aussiblue]

Can also sometime bedirt and grime on the splines on the drive shaft where it goes into the trans. An easy test is to give it (the front splined end) a soak with CRC or WD40 and see it temporarily goes away. The long wheel base cars are prone to this issue and dips in the road etc change the drive shaft angle change slightly and can make the noise change or go away.

[champ]

Hmmmmm...... Interesting. Now someone else tells me it could be diff bearings?????? Don't know...will wait & see what my mechanic man Davo says.

[champ]

Hello people, I'm back.... the humming noise?? Well I've got everyone "guessing" wheel bearings from 2 ford dealerships to a private mechanic who says could be "diff bearings". Tonight, on the way home we have developments... have started having a "clunk" every time the car goes over a bump or a dip as well as the motor doing a shudder when I come to a complete sudden stop. I am so over this, I should just get the sledge hammer & fix it properly & then just buy a new car! We shall see.... Chapter 2 after Friday when Davo has a proper look! stay tuned. he he

[mik]

sounds like you just need someone that can diagnose it definitively for you.

[champ]

I rekon. Times like this I wish I did what I wanted... which was to be a mechanic but there were no girl mechanics in the 80s... well not too many. Davo knows his stuff, but he's so hard to get in... Good mechanic, too many customers story. Never mind, will deal with the truckster for a couple of days...

[champ]

Update everyone!!!! Had the wheel bearings done, all four mind you.... Idler pulley, some belts & stuff, and now silence of the lambs. Yay!!!!