Bad popping/thumping noise from front end, 2006 Tahoe

[nonickatall]

The question is: Is the sound increasing with speed, or engine acceleration? Or is it connected to wheel rotation?

If it comes from engine or body mounts it must be louder on bad roads.
If it comes from engine, it must be connected with engine rpm.
If it comes from drivetrain like transmission, transfer case, differential or drive shaft/axles it must be speed connected.

Please describe, or do a footage and upload it to youtube.

 

[Filterless]

The question is: Is the sound increasing with speed, or engine acceleration? Or is it connected to wheel rotation?

If it comes from engine or body mounts it must be louder on bad roads.
If it comes from engine, it must be connected with engine rpm.
If it comes from drivetrain like transmission, transfer case, differential or drive shaft/axles it must be speed connected.

Please describe, or do a footage and upload it to youtube.

The sound is connected to speed - it only does it when speed is >40mph and only after a few miles warming up. You can be under power, cruising or coasting, and you’ll get the seemingly random ‘thump’ or ‘clack’ - this can be on smooth highway, (T/C in 2H) with no bumps at all. It increases in the amount of time it does it once it starts, but it’s not constant. It’s like something heats up and expands and starts to bind/bang inside something. Will try and get a recording. It also has a faint metallic, clacking sound to it. Hmmm!

 

[wjburken]

Can you feel it or just hear it? If you feel it, is it in the steering wheel, floor board, seat, etc?

Might be along shot, but might check under the hood to make sure the deflectors around your radiator/fan are all snug and secure.

 

[Filterless]

Can you feel it or just hear it? If you feel it, is it in the steering wheel, floor board, seat, etc?

Might be along shot, but might check under the hood to make sure the deflectors around your radiator/fan are all snug and secure.

Good advice, thank you.

You can only hear it, no feeling. It seems to come from the middle, under the drivers seat or front floor area. Checked all the fan area/under the hood, etc (E Fans) and everything else I can think of. There does seems to be a little play in the output shaft for the front axle - at the transfer case end, there is none at the front diff end. (All new u-joints also, they are solid.) How much play is normal there? I assume none…which is leading me to the T/C as the culprit…

 

[Owen]

2005 Tahoe here - I’m chasing the exact same noise, under the same conditions. It never does it just driving slow around town, but after 2-3 miles of highway speed (55-65) - it warms up…and then clunk - pop…off it goes. I think it must be something in the transfer case. I’ve checked and replaced all the u-joints, shocks, CV axles, etc etc. I’ve been under the truck often, wiggling and checking everything else very carefully. It must be driveline related. Truck is at 160k miles and in fairly good condition, no real rust. Frustrating, but I think a new case is the next step. :/
Ps. I had the same issue with the Service 4WD, it was a simple fix, the encoder motor position ring. Did it 2 years ago and never had a problem since.

Does yours do it every time you drive it? I haven't heard a peep in the last 150 miles or so. I'm starting to think it's either transfer case or front diff related. I was reading up about the possible "service 4wd" fixes and there's a few things im going to try and do and see if that helps because I'm thinking that its directly related to my issue. Ill check the encoder motor position ring though, thank you.

 

[Owen]

Can you feel it or just hear it? If you feel it, is it in the steering wheel, floor board, seat, etc?

Might be along shot, but might check under the hood to make sure the deflectors around your radiator/fan are all snug and secure.

For me, I can hear it and feel it. It's definitely coming from under my feet or in the front end.

 

[xylan]

GM issued a Service Bulletin for C6 Corvettes that had a similar problem. The cause was the wrong and/or inadequate grease on the CV splines going into the diff. The splines would bind and cause a 'popping' noise. You might try to get a dealer to look up that bulletin and find out exactly what grease they used to fix the problem.

Mine was under warranty, and I never asked them what grease was used, but it's a specific grease from GM for this application.

 

[Owen]

The question is: Is the sound increasing with speed, or engine acceleration? Or is it connected to wheel rotation?

If it comes from engine or body mounts it must be louder on bad roads.
If it comes from engine, it must be connected with engine rpm.
If it comes from drivetrain like transmission, transfer case, differential or drive shaft/axles it must be speed connected.

Please describe, or do a footage and upload it to youtube.

Originally I thought it wasn't impacted by speed, but it definitely is. My noise is basically exactly described as "Filterless"

 

[nonickatall]

The sound is connected to speed - it only does it when speed is >40mph and only after a few miles warming up. You can be under power, cruising or coasting, and you’ll get the seemingly random ‘thump’ or ‘clack’ - this can be on smooth highway, (T/C in 2H) with no bumps at all. It increases in the amount of time it does it once it starts, but it’s not constant. It’s like something heats up and expands and starts to bind/bang inside something. Will try and get a recording. It also has a faint metallic, clacking sound to it. Hmmm!

Sounds to me me that something is loose and bang in the drive wind... Ich would carefully check the bottom off the car. Probably a heat cover of the exhaust wich is not proper mounted... Sounds not that it comes from drive line or engine...

From my experience sounds which occur direct on the body, can be very loud inside, even if they have a weak reason...

 

[Filterless]

For me, I can hear it and feel it. It's definitely coming from under my feet or in the front end.

On *most* drives it will do it, but I live in a city, and it will never do it driving slow, no matter how much I drive. But once I hit the freeway, 50-60mph within 4 miles - clunk. Then nothing, then maybe an again a few more times, until I stop and go slow, then it’s gone. Same locations for me. I can shake the front drive shaft and it will wiggle at the front transfer case output end, but solid at the diff end. I think it’s the case, or like you said - the front diff - but I am going to change the case first.
Is it random for you? Highway speeds? Super annoying at any rate.