Weird Humming Noise at 42~45mph.Please Help

[240mph]

ok there is a very irritating humming noise when the mph reaches 42~45.i taught it could be low differential fluid but i changed it and its still making that noise. its really hard to tell where it comes from be cause when my car is on stands then it sounds like its coming from the tranny but when its on the road it sounds like it coming from the the passenger rear.and the passenger rear has really bad camber how can i fix that also.someone please help thanks in advance

[240mph]

no one ever experience this problem??????????????

[Weirsy]

ok im gonna go way out on a limb and ask if theres any vibration to acompany the hum......i found in my olds achieva around 50 mph the car would resonate until i acceled to around 55 or 60...

[JapaneseAutox]

mine does that too. i think it's just the exhaust piping vibrating in accordance to that certain rpm. mine happens in 4th gear around 2500rpm

[Weirsy]

well re learned in physics that everything vibrates at a certain point once it is connected to sumthing vibrating at the same frequency...lol this is probly over some or ur heads becuase weve been learing this stuff latly, but when the tires on the oad begin to vibrate at the same frequency that the frame of the car is supposed to it is called resonating...thats probly not ur problem...i have no clue tho

[uno]

my exhaust hums at 2500 in every gear...i dunno why, it used to make me mad, i just learned to live with it. I think it might actually be the plastic gaurd around the gas tank/trunk pan, that's all i see that it could be from looking under the car.

[240mph]

so does anybody know what the problem is

[s14 blacktop]

did you inspect your driveshaft?
get it up on a lift so you can go under it and look at everything ...
the closest thing I had experienced to this was that my transmision mount was torn apart. When your under the car push the tranny up and inspect the mount if it broke /seperated...

[supers0nic]

it could be your bearings, my friend had the same sound, a humming, turned out to be his bearings. but his was a subaru and they tend to do that, i dont know just a suggestion. :goyou:

[skatanic28]

tire out of balance or wheel bearing starting to go.
thats what its always been for me so far.

[idlafie]

ok there is a very irritating humming noise when the mph reaches 42~45.i taught it could be low differential fluid but i changed it and its still making that noise. its really hard to tell where it comes from be cause when my car is on stands then it sounds like its coming from the tranny but when its on the road it sounds like it coming from the the passenger rear.and the passenger rear has really bad camber how can i fix that also.someone please help thanks in advance

Fix your camber with the following eccentric bolts & spacers, (scroll down after the page loads)
http://www.pdm-racing.com/products/suspension.html
Chances are it could be your camber thats causing your irritating hum. The hum is probably coming from your tires. Notice any irregular pattern wear on the tire tread??
Anyhow, hope this helps...
ID
'95 SE

[240mph]

thanks for all the replies. i was first thinking it was the wheel bearing but when yo think about it if the wheel bearing is going out shouldnt it continously humm all the way instead of just the 4th gear.


idlafie: have you ever tried out those bushings. see the thing is with my camber problem on one side it is like how all 240's have but on the other side wear i got in to a accident before( which is also the side where the humming kind of sounds like it is coming from) the camber is really bad do you think those bushings will actually help it or do i need to get those rear adjustable camber upper arm.

[skatanic28]

right now mine hums from 45-55, no matter what gear. i jacked it up and my tire has some play in it from top to bottom. all the suspension links are tight so im just gonna replace the hub soon. give that a shot first, at least youll know for sure. i believe once the bearing wears more it will start to hum louder and more often.

[idlafie]

thanks for all the replies. i was first thinking it was the wheel bearing but when yo think about it if the wheel bearing is going out shouldnt it continously humm all the way instead of just the 4th gear.


idlafie: have you ever tried out those bushings. see the thing is with my camber problem on one side it is like how all 240's have but on the other side wear i got in to a accident before( which is also the side where the humming kind of sounds like it is coming from) the camber is really bad do you think those bushings will actually help it or do i need to get those rear adjustable camber upper arm.

Nope...never tried the bushings...yet that is!! I have a subframe I pulled out of a 97 SE parts car that has them pressed in...sooooo... I may be installing them soon. My understanding though is that the eccentric bolts & camber bushing are for a car that's had the suspension dropped & riding on WIDER tires. Supposed to help with tire wear. Since I'm only running 225/50/16 with a 1" inch drop, it really won't make much of a difference on my car.

HOWEVER since you mentioned you got into an accident before on the side where the humming sound is coming from, the force of the accident may have killed your wheel bearings. If you had your car repaired thru an insurance claim, (either your insurance company or the other person that hit you insurance company), call the company up & ask them to reopen the claim. Tell them you found additional damage that was not found at the time your car was repaired. You might have to argue with the claims adjuster about the repair cuz he'll probably say it's wear & tear. You'll just have to respond that the damage occurred at the time of the accident & was not discovered till now.
Anyhow...good luck!!
ID

[240mph]

i have a new wheel bearing i might try that out but hopefully thats the problem. the weird thing also is that when i put my car on stands and cant seem to find exactly where the noise is. i might try to take out the driveshaft and spin it 180 it might be in the wrong side or something when i changed my clutch before.

[s14 blacktop]

did you change your cluch before the accident or after?

[240mph]

i did it after. i still can figure out the problem

[s14 blacktop]

ok I dont know if I asked you this or not but did your car make that noise after you had your wreck or after you changed your clutch.
I'm betting its your clutch thats making that noise see my car used to make that noise but only at startup and it would go away after I put it in gear.
I never had time to mess with it since I got a sr20det, but it sound like your transmission is at fault.
Oh yeah did you change it yourself or you had somebody else do it?

[240mph]

actually i started to notice after the accident. and yes i changed the clutch myself. do you think i should rotate the driveshaft?

[s14 blacktop]

no I dont think its the driveshaft anymore..
it might just be your transmissions 4th gear, if it was you drive shaft it would make a noise and get louder with your speed. That same rule goes for anything behind the tranny(ex. diff,axles and etc..).
I think your fourth gear is on its way out!!!
buts thats just my opinion.

did you check your transmission motor mount???
cuz besides what I mentioned earlier this is the only other thing that it could
be, that I know about...

Or I could be wrong!!!

[240mph]

i dont think its my 4th gear going out because it can go in and out smoothly. if it was going out it would grind. ill try to check my trans mount

[Matlock-gtr]

i have a similar problem.. check your driveshaft support bracket... get under the car and see how much slack it has.. shouldnt have much.. mine has some excess slack so i think that is my problem at least... i havent gotten around to replacing it.. but i talked to some mechanics who thought it could definately be a source of vibration around those speeds

[240mph]

which shouldnt have slack the driveshaft or the bracket thanks