Possible front diff failure?

[Geotrash]

Here's my question... I do primarily hear it form the transfer case but I dont see that kind of movement from the rear driveshaft when doing the same thing, would the slack in the chain cause that?

Same with my '07 XL Denali. I only see that kind of play on the front driveshaft because that's the shaft that's driven by the chain inside the transfer case. The rear driveshaft is direct-driven off the transmission output shaft, so any play in the rear differential isn't going to be felt by trying to turn the rear driveshaft. That's why I say it's important to get a stethoscope on that transfer case, so you can confirm that that's where the noise is coming from. Super common to have that much slack in the transfer case chain on higher mileage AWD GMT900 rigs, by the way.

 

[petethepug]

Congrats from SoCal on the 08. Welcome to the benefits of the 07/08 L92 6.2L motor without AFM/DOD.

Info below on an owner of two 07 Escalade ESV. One was a business Limo. TLC is an understatement on the Resto of his vehicles. You’ll pick up almost every detail you need on your truck here…

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Did you press new bushings into the front diff mounts or buy new ones? ChiefM pressed in new bushes the 1st time and they failed. He ended up purchasing the entire assembly because they’re cheap. It fixed the clunk.



He also used a rebuild kit on the xfer case @ 200k mi. He wasn’t 100% pleased w/ the rebuild and swap’d in a low milage used unit. That cured the rest of the clunk.

 

[Discodisco]

Ah, that's not too bad at all. That's not 180º, which would have been excessive. Next step: get a cheap mechanics stethoscope from autozone and do exactly what you recorded but with the tip of the 'scope on the front diff housing, then the transfer case, then the diff mount areas to pinpoint where the clunking noise is coming from. My bet is it's backlash in the transfer case chain.

Here's my question... I do primarily hear it form the transfer case but I dont see that kind of movement from the rear driveshaft when doing the same thing, would the slack in the chain cause that?

Congrats from SoCal on the 08. Welcome to the benefits of the 07/08 L92 6.2L motor without AFM/DOD.

Info below on an owner of two 07 Escalade ESV. One was a business Limo. TLC is an understatement on the Resto of his vehicles. You’ll pick up almost every detail you need on your truck here…

Loading…

www.cadillacforums.com

Did you press new bushings into the front diff mounts or buy new ones? ChiefM pressed in new bushes the 1st time and they failed. He ended up purchasing the entire assembly because they’re cheap. It fixed the clunk.

View attachment 440917

He also used a rebuild kit on the xfer case @ 200k mi. He wasn’t 100% pleased w/ the rebuild and swap’d in a low milage used unit. That cured the rest of the clunk.

I used the complete bracket, you can see in the video its def not moving the diff housing around, what you guys are saying makes a lot of sense, I might just buy the chain and seal kit and crack it open. The sound is def louder at the transfer case even without a stethoscope I can tell.

 

[Geotrash]

Here's my question... I do primarily hear it form the transfer case but I dont see that kind of movement from the rear driveshaft when doing the same thing, would the slack in the chain cause that?

See my answer to that in post #11 above.

 

[petethepug]

I think @swathdiver was going to have his xfer case rebuilt recently. Maybe he has some recommendations based on his experience.