Strangest drive train noise w/ video

[Clooney]

Cant make out what this noise is on my 03 TB 4x4. The first 60 seconds of this video its very noticeable, almost like I have a bad tire. Its a wobbling noise. Not sure if its a front drive axel, a wheel bearing or what. Anyone heard this before? The truck is on a supreme 3 inch leveling kit with 30 inch BF Goodrich KO2 AT tires.

 

[gmcman]

Did this happen all of a sudden, or have you had the "mud tire" sound for a length of time?

Sounded worse when making a right-hand curve, quieted down when driving to the left.

My guess based on that is the front hub and bearings.

If they have around or more than140-150K miles then that's likely the culprit.

With that much noise if it is a hub and bearing then you might even have movement when trying to move the tire (grabbing the tire at 12 & 6 O'clock) when it's off the ground.

Are your tires cupped?

 

[Clooney]

Did this happen all of a sudden, or have you had the "mud tire" sound for a length of time?

Sounded worse when making a right-hand curve, quieted down when driving to the left.

My guess based on that is the front hub and bearings.

If they have around or more than140-150K miles then that's likely the culprit.

With that much noise if it is a hub and bearing then you might even have movement when trying to move the tire (grabbing the tire at 12 & 6 O'clock) when it's off the ground.

Are your tires cupped?

It started happening after I put air in the left front tire. It was down about 20 pounds from where i normally run them (70psi). There seems to be a little cupping, but nothing major. I jacked up the front left side and didnt notice any play at 12 and 6.

 

[gmcman]

It was down about 20 pounds from where i normally run them (70psi)

70???

30x9.5-15 KO?

If so, they have a max inflation of 50 PSI.

I jacked up the front left side and didnt notice any play at 12 and 6.

What about the RF?

How even is your treadwear? I'm guessing the edges have more tread than the center.

 

[mrrsm]

For OEM Tires...The attached image comes straight from the Trailblazer Owner's Manual indicating a MAX at Cold Temps of 38 PSI.:

The Over-Inflation issue would explain why that Tire is Over-Rebounding at Highway Speed and playing Hell with the Shock Absorber trying very hard to overcompensate for the Coil Spring' dealing with that Extra Bounce from having way too much Air Inflation.

And from THIS Link:

Tire Cupping: Causes, Problems, and Prevention

www.bridgestonetire.com

CAUSES OF TIRES CUPPING

Tire cupping can be a symptom of a variety of suspension issues. Getting them corrected promptly can help owners avoid extra tire and repair expense.

Misaligned Tires

Misaligned tires’ contact with the road may be uneven, or they may not be rolling straight. The uneven stresses on the tire caused by these conditions may show on the tread as cupping, or a “saw-tooth” wear pattern at the edges of the tread - “heel-toe wear” in engineering-speak.

Worn Suspension and Shocks

Suspension components like shock absorbers, struts, bushings and others wear out with miles traveled. The result can be a tire that is no longer able to roll smoothly down the road; instead, it bounces slightly. This bouncing creates uneven points of pressure on tires, leading to tire cupping.

Unbalanced Tires

If weight across the circumference of a tire is not evenly distributed, it could lead to unbalanced tires. If severe enough, an out-of-balance condition can cause some sections of the tread to meet the road with greater force than others. This increased force results in greater wear in those areas - tire cupping or erratic tread wear.

 

[Clooney]

I'll post some pics of the tire condition and their PSI requirements later on. When I mounted the tires and went to inflate them I was shocked to see the PSI reading on the tires were something like 55-80PSI. Unless I misread them, that's what they read. I see on their website that 265/70 17 tires max PSI is 50 but that's not what is on the tire itself.

 

[Chickenhawk]

Getting to the bottom of this. They sold you the wrong tire ... but strangely enough, it might not have been their fault. If you check the specs on BFG's website, that tire is listed as max load of 1400 pounds for the 80 psi version. The 50 psi version is 1100 pounds. Both those numbers are shockingly low. I did some more checking, and the load ratings from BFG are WRONG. Your 80 psi version is rated at 3000 pounds, and the 50 psi version is rated at 2400 pounds. 2400 pounds is way more than you need anyway, so they should have sold you the 50 psi version.

LT (light truck) tires have much stiffer sidewalls to carry a greater load, but unless someone is hauling a load FAR in excess of our rated Gross vehicle weight, even P (passenger) tires are sufficient. If you do some off-roading, and it appears you do, then LT tires are also useful because the sidewalls are stronger and more resistant to rock damage.

If I were you, I would deflate them to 50 psi and see if the sound changes. I would also guess you have a slow leak in that one tire, and as far as the sound is concerned, it still might be a wheel bearing. Just one caution on wheel bearings on our platform: if it sounds worse when turning to the right, it might NOT be the left hand wheel bearing, like a more traditional diagnosis would tell you. Lots of us - myself included - have been fooled by this. I would buy TWO new wheel bearings. (I replaced both sides with the new Mevotech TXK bearings as they seem very high end.)

Plus, with a lift, you will go through wheel bearings faster anyway.

 

[Clooney]

Well, its not the tires. Just put a brand new set of BF Goodrich KO2's on it, took it for a drive and the sound is still there. So looks like I will be buying the wheel bearings next.

Could it be a CV axel as well?

 

[gmcman]

Could it be a CV axel as well?

They don't usually sound like a mud tire, more of a click on turns.

 

[Clooney]

Getting to the bottom of this. They sold you the wrong tire ... but strangely enough, it might not have been their fault. If you check the specs on BFG's website, that tire is listed as max load of 1400 pounds for the 80 psi version. The 50 psi version is 1100 pounds. Both those numbers are shockingly low. I did some more checking, and the load ratings from BFG are WRONG. Your 80 psi version is rated at 3000 pounds, and the 50 psi version is rated at 2400 pounds. 2400 pounds is way more than you need anyway, so they should have sold you the 50 psi version.

LT (light truck) tires have much stiffer sidewalls to carry a greater load, but unless someone is hauling a load FAR in excess of our rated Gross vehicle weight, even P (passenger) tires are sufficient. If you do some off-roading, and it appears you do, then LT tires are also useful because the sidewalls are stronger and more resistant to rock damage.

If I were you, I would deflate them to 50 psi and see if the sound changes. I would also guess you have a slow leak in that one tire, and as far as the sound is concerned, it still might be a wheel bearing. Just one caution on wheel bearings on our platform: if it sounds worse when turning to the right, it might NOT be the left hand wheel bearing, like a more traditional diagnosis would tell you. Lots of us - myself included - have been fooled by this. I would buy TWO new wheel bearings. (I replaced both sides with the new Mevotech TXK bearings as they seem very high end.)

Plus, with a lift, you will go through wheel bearings faster anyway.

I went ahead and ordered 2 of these. This is the part number you were talking about right?

 

[Chickenhawk]

That is the lower end Mevotech. Like most other aftermarket parts, there are two tiers: economy and premium.

This is the one I used:

 

[Clooney]

That is the lower end Mevotech. Like most other aftermarket parts, there are two tiers: economy and premium.

This is the one I used:

Ok, I'll add those to my wish list on the next go around.

Thanks for all the help guys, much appreciated!!