2014 Yukon Denali/Soft clicking or thumpingound from front differential

[Shorrsteve]

I just bought a 2014 Yukon Denali. I know this sound is from the front differential. It sound exactly like a bad belt on a tire. Its a dull Clicking.. its not transfering to the steering wheel. Its quiet when car is in neutral & moving. Louder under a load. What is it in the front differential that can make a rotational soft thumping?​

https://www.yourmechanic.com/services/clicking-or-popping-sound-is-coming-from-wheels-inspection

 

[swathdiver]

I just bought a 2014 Yukon Denali. I know this sound is from the front differential. It sound exactly like a bad belt on a tire. Its a dull Clicking.. its not transfering to the steering wheel. Its quiet when car is in neutral & moving. Louder under a load. What is it in the front differential that can make a rotational soft thumping?​

https://www.yourmechanic.com/services/clicking-or-popping-sound-is-coming-from-wheels-inspection

First place I'd look is the hubs. Get the front wheels off the ground and see if there is play when you hold tire at 3 o'clock and 9 o'clock and give it a shake. Same for 12 and 6. Does the sound change when changing lanes, driving through a curve in the road or on turns?

Have you inspected the CV Shaft boots?

 

[Shorrsteve]

First place I'd look is the hubs. Get the front wheels off the ground and see if there is play when you hold tire at 3 o'clock and 9 o'clock and give it a shake. Same for 12 and 6. Does the sound change when changing lanes, driving through a curve in the road or on turns?

Have you inspected the CV Shaft boots?

I know the problem is in the front differential. NOT the CV joints or boots and NOT the hubs. It sounds like a broken belt in a tire. But the noise stops if the car in in motion and placed in neutral. The noisehets more pronounced when under a load.

 

[Shorrsteve]

I know the problem is in the front differential. NOT the CV joints or boots and NOT the hubs. It sounds like a broken belt in a tire. But the noise stops if the car is in motion and placed in neutral. The noisehets more pronounced when under a load.

 

[Geotrash]

I know the problem is in the front differential. NOT the CV joints or boots and NOT the hubs. It sounds like a broken belt in a tire. But the noise stops if the car in in motion and placed in neutral. The noisehets more pronounced when under a load.

How do you know that? I have decades working on 4WD vehicles and wouldn't be able to tell that without either getting the front end off the ground or putting a set of ears on it while driving.

 

[Shorrsteve]

How do you know that? I have decades working on 4WD vehicles and wouldn't be able to tell that without either getting the front end off the ground or putting a set of ears on it while driving.

Thank for asking. I know it because when I put a stethascope on the front differential, with the car on jacks. Thats where I hear the noise. So is it a gear or a bearing in the differential. As I said it only makes noise under a load. The sound matches the rotation of of the wheel?

 

[swathdiver]

Thank for asking. I know it because when I put a stethascope on the front differential, with the car on jacks. Thats where I hear the noise. So is it a gear or a bearing in the differential. As I said it only makes noise under a load. The sound matches the rotation of of the wheel?

Where on the differential did you put the stethoscope and hear the noise loudest? Out on the axle tube on the passenger side or on the driver's side of the pumpkin?

 

[Shorrsteve]

Where on the differential did you put the stethoscope and hear the noise loudest? Out on the axle tube on the passenger side or on the driver's side of the pumpkin?

Good question! I only confirmed the noise was in the differential. The problem is, with out a load on the differential. The noise is pretty quiet. When driving its much louder. And up a hill the sound is much more pronounced.

 

[Bill 1960]

If it’s in sync with tire rotation could be a defect in the ring gear. A visual inspection with the front cover off would be my next step. A look inside at the condition of the oil and internals will tell you a lot.

It is also possible you’re hearing a noise at the diff that originates in a hub or CV. Noises easily telegraph throughout the drivetrain and I don’t think you’re putting a stethoscope on a CV in motion?

It’s probably not the driveshaft or TC since your noise syncs with tire rotation. Those would be 3x faster.

Check out the front diff mounts too.

 

[Geotrash]

If it’s in sync with tire rotation could be a defect in the ring gear. A visual inspection with the front cover off would be my next step. A look inside at the condition of the oil and internals will tell you a lot.

It is also possible you’re hearing a noise at the diff that originates in a hub or CV. Noises easily telegraph throughout the drivetrain and I don’t think you’re putting a stethoscope on a CV in motion?

It’s probably not the driveshaft or TC since your noise syncs with tire rotation. Those would be 3x faster.

Check out the front diff mounts too.

+1. This is why chassis ears are so useful. I have them on my Christmas list this year - they will pay for themselves with a single trip to the shop for diagnosis.

The only thing I can think of that would cause that kind of noise inside the differential is as Bill suggests, a defect in the ring gear. Pinion bearings give a rhythmic grinding/growling sound when they're on the way out, and axle shaft bearings usually make a low-pitched humming sound.

It's worth pulling the cover to take a look. If you decide to do so, it's wise to loosen the fill plug on the side of the differential before you remove the cover. They're notorious for being impossible to remove and people strip the corners off the hex head of the thing trying. Better to do that while it still has fluid in it and is drivable than after you drain the fluid and have no way to put more in it.