humming/whirring noise at speed

[flyweed]

Ok guys..I'm at a loss here. my 2004 Envoy XL has this "humming" or "whirring" type of noise..I notice it mostly at about 40mph and faster. It is really noticeable at 60mph. The sound almost reminds me of the sound a tire makes when a belt has slipped, or when it's rubbing against something..just a low humming sound that gets a bit higher in pitch as a speed up and lower as a slow down. I've replace almost ALL front end stuff recently, so not sure what it could be..I have brand new tires, new wheel bearings, new tie rod ends, had a full alignment done, and also replaced the entire front end Differential just before Christmas.

Not sure what's making the noise or why. Any thoughts??

Dan



I should also add..that the noise increases with speed of vehicle whether coasting, or giving it gas. It doesn't get louder or softer with more torque applied. It gets louder the fast the vehicle is moving whether up hill or down. Shifting into and out of all gears is nice and smooth, nothing jerky, or clunky.

 

[Blckshdw]

I know your weather right now might be an issue, but what I would do is try to get the thing on jacks, put it in neutral, and spin the wheels by hand. See if any of them seem to give a little more resistance than the others. Try to narrow down your area of troubleshooting somehow.

 

[The_Roadie]

How many miles, and are you religious about servicing the transfer case (assuming it's 4WD) every 50K. How about checking the oil level in the differentials?

 

[flyweed]

167,000 miles. do tranny fluid every 50,000 miles..and do the transfer case every 75,000 miles. Front Diff is new, new grease/fluids in that as well. Will be doing my tranny actually tomorrow again, as its due!

 

[flyweed]

and by transfer case do you mean the front axle disconnect assembly? I replaced that as well, when I replaced the front Diff. Both new

Dan

 

[The_Roadie]

 

[BC backroader]

My TB EXT has developed the same hum/whirr over the last week, related to road speed, not engine speed. It has become louder during the week, and increases when turning, especially a large radius curve, rather than a tight corner. I suspect it's a wheel bearing, and will have it checked out by a local mechanic that I trust in the next few days. I'll report back as soon as I know.

 

[HARDTRAILZ]

My TB EXT has developed the same hum/whirr over the last week, related to road speed, not engine speed. It has become louder during the week, and increases when turning, especially a large radius curve, rather than a tight corner. I suspect it's a wheel bearing, and will have it checked out by a local mechanic that I trust in the next few days. I'll report back as soon as I know.

Sounds like wheel bearing for sure. You get more or less noise turning different directions?

 

[flyweed]

BC-- yours is DEFINITELY wheel bearing..and an easy DIY repair if you are handy...I did both of my front bearings last year. Mine makes that SAME kind of sound..but it does not increase or decrease with turns..so turning does not affect the sound I am getting..only higher speeds.

 

[HARDTRAILZ]

I would still double check your wheel bearings. At a year old they may be shot again. Seems all brands of replacements have a pretty good fail rate on this platform. My last one had no change in cornering but gave me a mud tire kinda hum different than my normal and in checking the hubs I found one was starting to go.

 

[BC backroader]

Hardtrailz, it gets louder when in right hand curves, the increase is not as noticable in left turns.

flyweed, at one time, I did a lot of this kind of work myself, but I now live in a condo with underground parking, and the strata council is paranoid about oil spills on the concrete, so does not allow wrenching your own vehicle in there. I'm also getting a lot less limber, so getting under the truck is no fun anymore. One of the many joys of passing your 70th birthday!

 

[flyweed]

Hardtrailz...damn..your kidding..my less than a year old bearings may be going south???? That would suck. I mean..it's not a terrible job to replace, but still. So should I jack up the front wheels and give them a spin and see how freely they spin, and if it makes any kind of noise at all??

Dan

 

[jpinoy]

Hardtrailz...damn..your kidding..my less than a year old bearings may be going south???? That would suck. I mean..it's not a terrible job to replace, but still. So should I jack up the front wheels and give them a spin and see how freely they spin, and if it makes any kind of noise at all??

Dan

Do you have any updates on the issue?

I'm experiencing the same issue you mentioned. I've replaced both front wheel bearing, cv axle disconnect(complete kit). I also just changed out both my struts since it was due.

What I did notice was after changing out the cv axle disconnect, when I put it in 4-low, my stabilitrack light blinks(3-4 times??) and then stays on. But that is only in 4-low. I maybe switched it to 4-low once just to make sure it worked(before replacing my cv axle disconnect), and didn't pay it any attention.

I'm still hearing the humming noise.... I've already changed out the front/rear differential fluid and transfer case fluid.... no change in sound... and it does sound like it's comming from the front passenger side. I know my wife says she hears it pretty good on her side when we drive around...