High Pitched Wheel Speed Whistle or Squeal

[doubleclutch]

So it seems that when I let off the gas or am lightly on the gas I get a high pitched whistle noise from the front of my car. It is not engine speed and does not happen at idle or reving and letting off the throttle at idle. It seems to start happening after 10 mins driving or more.

I checked the trans fluid oil level and the transfer case oil level as I read on here that that may be a cause. Both were full. The trans was dirty but reasonable, the transfer case was very dark/burnt. (see attached picture(sorry about the hideous table cloth)).

I have read that these may be vacuum leaks but not sure how it could be since it doesn't change with rpms only vehicle speed.

any help would be appreciated.

Thanks

 

[Colt4G63 also]

Sounds like you may be describing gear noise. In the old days they used to pack the rear end with bananas, but with all the gear lubes available today, you might try some shockproof in the transfer case, and MT85 or MT90 in the transmission.

 

[spyderdrifter]

Change the gear oil. Don't over fill it though. If it persists, you may have to pull the t-case and trans to inspect things, if you think it's one of those parts.

 

[doubleclutch]

definitely not the rear end. Comes from the front like i mentioned earlier. I have MT-90 on order just waiting for it to show up. The only other thing i could think of was wheel bearing. I will be doing the "is it hot?" test tomorrow. transfer case definitely looks worse off than the gear box at least by fluid color.

edit: Seems like it is always there even under throttle. Also seems to be less prevalent in reverse.
Edit: wheel hubs didn't seem to be hot even after 30 mins of highway driving. I may pull the wheels to look at them anyways.

 

[doubleclutch]

I tore the drivers side down to the hub today after still not being able to determine anything. Seems like there is some clunking as I spin the hub by hand.

I can't think of anything that should be clunking/popping in there. Even with the wheel turned the CV should be smooth.

Any thoughts?

 

[smills1840]

I'm having a nearly identical problem. The noise starts once I reach 25 MPH, and changes frequency with speed. It's a very high pitch squeal, and I'm almost positive it's on the driver's side. I don't think it's related to the engine, because as the OP said the noise still persists even when idling at speeds over 25 MPH. Applying the brakes has no effect, until slowing the car below 25.

 

[5150DSM]

Sounds like a possible wheel bearing to me. Simple test, jack up the front with the wheels on, grab the top and bottom of the tire and rock it back and forth. (toward and away from the car) If there is play and/or a clunk as you rock the tire, the wheel bearing is a good bet

 

[fonzi90Tsi]

I have the same problem. Going yo change all fluids Sunday.

 

[doubleclutch]

Got both wheels hubs in. Seems to have fixed the problem but I need to get it out for a longer drive and heat things up before I put it to bed. Definitely rides quieter. Makes me want to do the rears too.

Edit: squeal is still there. I can't think of anything else it could be other than the carrier bearing on the drivers side, unless it is internal to the trans. Any thoughts?

 

[smills1840]

Did anyone ever find the cause of this? It's driving me nuts now that it's warm enough to roll down the windows.

 

[doubleclutch]

So I completed a transmission and a transaxle fluid change with MT-90 and there is no difference in the squealing noise. I crawled under the car after I could hear the noise and tried to check the temperature of the intermediate axle bearing and it didn't seem to be any hotter than I would expect since it is bolted to the engine.

I an pretty much out of ideas at this point and really don't want to take it to a mechanic...any other ideas?

 

[greydelta38]

Anybody have any info about this? I'm having the same problem. When I roll the windows down and pass by another car, I can hear a type of rattling/scraping noise. The best way I can describe it is that it sounds like a wire brush is scraping the tire as it spins. I got told by a mechanic (that I trust) that it is in fact a transmission problem, even after I mentioned it sounding like a wheel bearing. I don't have the know-how or the wallet to replace an entire transmission right now, and he says he can't be entirely sure what it is without dropping the tranny and looking at it. Somebody has to know what the hell this is. I'll start a new thread if no one can give an answer, because the all knowing Google hasn't been any help.

 

[Boostdriven]

Any chances that its coming from the brakes, after you drive it for a while things heat up and expand so its possible the noise is coming from the brakes. Maybe the pistons in the calipers don't retract like they should causing friction on the pads against the roters more then usual.

 

[greydelta38]

Any chances that its coming from the brakes, after you drive it for a while things heat up and expand so its possible the noise is coming from the brakes. Maybe the pistons in the calipers don't retract like they should causing friction on the pads against the roters more then usual.

It's definitely not the brakes. I wish it were that easy. Usually when I notice it, I'll be on the highway in the lane next the median, and roll down my windows. If I have the windows up, it's too faint to hear. I'm still crossing my fingers that it's just a bearing that is unusually loud. I'm heading down there in 30 minutes to see what he found, will report back later to get you guy's opinions on what he said.

 

[Boostdriven]

Next time you drive the car on the highway roll your windows down and as you drive next to a median drop it in neutral and listen for that noise, you can even shut off the engine to quiet things down a bit. If the noise goes away when the engine is off and the car is in neutral then its probably the tranny, if not then I would investigate the brakes or possible the wheel bearings.

 

[doubleclutch]

Boost, if you have read the post, I have eliminated brakes and wheel bearings. There is no change in the noise when the brakes are on or off and whether the brakes are cool or not. I also have replaced the wheel bearings and relubricated the caliper slides.

Also, it does in neutral or engaged. No difference.

 

[Boostdriven]

Sorry I was more referring to what greydelta38 was saying. You were in the works of testing different things so I tried to help him out.

Now when you drained the tranny oil did you see any metal flakes in the oil. Any unusually large flakes could indicate that bearings are going out.

 

[Lou98GSX]

if noise changes when your on and off the gas then the problem is most likely in the trans . there is also a bearing on the left side axle that you can check that could also be bad .

 

[greydelta38]

Okay, good news and bad news. I replaced the transmission fluid, and the clutch problem seemed to go away. cheers. However, the scraping noise is still present. My guy said that it looks like it's a transaxle problem, which will run into 4 digits on the bill in no time. The good news is that it seems to not be a humongous issue for the time being, so I have a while to save my pennies for a new transmission if a rebuild isn't possible. Apparently, all it is at this point is an annoyance. Anybody want to elaborate for a person who doesn't know transmissions well?

 

[doubleclutch]

looked like it was the original fluid. No large flakes that I saw and I took a pretty good look. Also, i would say that large flakes are likely not from bearing as bearings usually fail by pitting and scoring which actually welds the removed material back onto the roller.

the intermediate bearing on the left axle I think is the culprit I just can't figure out a way to test it without tearing the whole half of the front drivetrain down. I have Pmed a couple of guys who have had and fixed the same problem but haven't gotten responses yet. I may just have to take one for the team and see what happens

 

[Boostdriven]

True but once the bearings get pitted they start to make noise. My dads Honda had a worn out input shaft bearing that was making noise but once we replaced it the noise went away. It can be difficult for us to figure out some of these problems without actually being there to see what's going on. Hopefully its a simple fix in your case and you get it figured out.

 

[smills1840]

My noise still persists even with the engine off and the car in neutral. So what does that rule out?

 

[Boostdriven]

I would say it rules out the input shaft bearing. If I remember correctly its the smallest bearing inside the tranny and on that of that its in constant use if your engine is running whether your driving or sitting at the stop light. If your noise is speed related then I would says its something with your wheel bearings or driver side axle shaft carrier bearing. Wheel bearing noise will typically change a bit if you swerve left then right a little bit as you're driving. I had a car before that had a bad wheel bearings on the front passenger side. As I would swerve right the noise would get quieter because there was less load on the right side and as I would swerve left the noise would get louder because there was more load on the right side. Carrier bearings on your axle or the drive line are not effected by swerving left or right. Not every car is the same but those are some of the basic ways of possibly finding a problem.

 

[doubleclutch]

Well I am taking a guess that it is the carrier bearing. For 60$ from JNZ with the seals and everything shouldn't be too bad. I will let you know how the install goes (could be a pain) and if it fixes the problem. Should have it done in the next week or so.

 

[talon_42o]

I think I have the exact same problem the noise is like a wheel bearing noise but when I turn left or right no changes in pitch or anything. Same if the car is in gear or not it seems to be based on vehicle speed only I noticed some grease leaking from the boot near the carrier bearing, my axel does not make any noise turning or anything so I suspect the bearing on the axel support is bad. The trans shifts perfect and was rebuilt according too the previous owner... I'm trying too rule things out here thankfully I have a complete drivers side axel and carrier bearing from my talon that I am scrapping. I hope its not in the transmission. I have a Thermal R&D exhaust and the noise is louder then that at 80km/h I can't stand it.