Source of ugly sound

[Marinmcgreevy]

I hoping someone can point me in the right direction.

My H3 is making an intermittent sound. Not a good sound. I have not been able to find the source.

What I find:

sound source is in the engine bay. Drivers side.
Sound is not dependent on road speed or engine speed.
sound is being generated by something that is rotating.
Sound does not occur while driving under load
sound only occurs while coasting on level ground.
Sound does not go away if brakes are applied
water pump is not leaking
a/c compressor engaged/not engaged has no influence on the sound
noise sounds metallic but not with a lot of mass associated
cycling through transfer case locked hi lo has no influence

everything under the the hood looks ok. I have not been able to hear the sound while at idle. The truck has to be moving

My wife first detected the sound and when I drove the truck I got the sound. I immediately thought (but did no accuse) that she had run over something. No garbage can lids this time.

My my first thought was water pump or belt idler pulley but the sound is not engine speed dependent. Fan clutch is fine. Then perhaps something associated with the front axles but the sound is not road speed dependent.

The he sound will disappear for 200 miles at a time but will also start and stop during a single drive

i am stumped and do not want to just start replacing things. The sound is loud and I generally do not like to run anything to failure.

Any ideas would be hugely appreciated!

Evan.

 

[JPaul]

Can you describe what the sound actually sounds like other than metallic? Is it a grating sound? Clanking? Pinging? You mention coasting, is your H3 a manual or an automatic transmission?

 

[alrock]

I can't understand a sound that is dependent on neither road or engine speed but is dependent on something rotating. But I'm going to point to a few things that might make noise when coasting and not under acceleration: propshaft u-joint, propshaft CV joint, maybe front diff or CV axles.

 

[Marinmcgreevy]

The sound is like an old sheet metal radiator fan rubbing on a sheet metal shroud. Not plastic

 

[Happy Hummer]

Are we talking about the heat shield rattle?

 

[JPaul]

Are we talking about the heat shield rattle?

That might be it.

Sent from my Nexus 7 using Tapatalk

 

[Hunner]

What about the brake accumulator pump?

 

[4speedfunk]

Try power braking the truck in forward and reverse to induce the noise. If the noise appears it could be a motor mount.
Could also be a broken flex plate.

 

[Marinmcgreevy]

The heat shield was a good recommendation but that is not the source of the noise. I will check the brake accumulator pump. I drove around the other day and took some videos to capture the sound. I will try to upload. Again, the sound is very intermittent. The sound is loud enough that I will cause people on the side of the road to turn their head suddenly.

Thanks

 

[Marinmcgreevy]

Turn up the volume and cringe! AWFUL sound! [video=youtube_share;9H2vUE_iAJs]https://youtu.be/9H2vUE_iAJs[/video]

 

[delta88]

Turn up the volume and cringe! AWFUL sound! [video=youtube_share;9H2vUE_iAJs]https://youtu.be/9H2vUE_iAJs[/video]

That's your wheel bearing hub assembly.

 

[H3Wolf]

I agree with that, I would check that immediately, also anything around it.

Sent from my SM-G920V using Tapatalk

 

[napalmsticks]

After going off the beaten path this weekend I am getting a similar sound from my right front wheel though not as loud. It seems to be making the sound when I am braking or turning to the left thus loading the right tire. Additionally on the way home my ABS failure light lit up with the service stab system (went off once then came back on). Are you getting any lights in the dash? Pretty sure my hub is bad, they are pricey.

 

[Marinmcgreevy]

Wheel bearing hub assembly makes sense. Will go after that. Thanks to all!

 

[BIGFRY77]

Marinmcgreevy, DO NOT continue driving the H3 as your wheel bearing assembly could completely fail and cause the tire to literally come off of the vehicle. That sound is your bearing trying to lock up.

Napalmsticks, It is common for bad wheel bearing/hub to set of the ABS sensor as it is part of the assembly.

 

[napalmsticks]

Yes sir! I replaced both hubs last night, took me about 3 hours total. Very easy work with a big slide hammer and a can of PB Blaster. Noise is gone and ABS light is now out. The part of the sensor that goes inside the right hub was all chewed up from the internal ABS gear.

 

[napalmsticks]

Wheel bearing hub assembly makes sense. Will go after that. Thanks to all!

I got my hubs here:
https://www.amazon.com/gp/product/B0027A5L32/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

3 bolts per hub:
https://www.amazon.com/gp/product/B00HFLBS4Y/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

ETA:
Rent one of these from AutoZone or Advanced Autoparts:

 

[BIGFRY77]

A trick you can use to get them out is to take the bolts out then thread them in about 4 threads, use a pneumatic hammer chisel with a flat bit and hammer on the head of the bolts alternating the bolt you hammer on. This method takes about 2 minutes to get the hub assembly out even on the nastiest rust welded ones.

 

[Marinmcgreevy]

Thanks for all the help. The front end is pretty corroded. I have added some photos of when I replaced the front rotors last fall. The rotors were so corroded they split pin areas and felt like warped rotors. Will need to use a slide hammer.

 

[4speedfunk]

Jeez. Been driving in the ocean or what? That's got to be worst case of corrosion I've ever seen on a rotor.

 

[Marinmcgreevy]

How difficult was it to remove the hub attachment bolts? What did you do with the half shafts?

 

[Marinmcgreevy]

Michigan and Pennsylvania winters.

Jeez. Been driving in the ocean or what? That's got to be worst case of corrosion I've ever seen on a rotor.

 

[napalmsticks]

I used an impact for the hub bolts. Left the half shaft in, just back off the nut holding the half shaft to the hub. If you don't have a powerful impact loosen the half shaft nut while the truck is on the ground. I disconnected the tie rod end and upper a arm also to allow for play in the knuckle to get the impact on the hub bolts.

 

[BIGFRY77]

1/2" drive ratchet and a pivoting impact socket typically always works. Spray free all on both sides of the bolts let sit for a few minutes apply more free all and a lot of elbow grease... Oh and yes take the spindle nut off and lightly tap on end of the spindle with a hammer, use a piece of wood between the hammer and spindle so you don't mess it up, do this before taking the hub bolts out. As napalmsticks said just let the axle shaft sit there.

 

[Marinmcgreevy]

Thanks to all for the help. Only DS wheel bearing was bad but it was toast.