The Clunk that was Not the Drive Shaft Slip Yoke - Solved

[petethepug]

The info here that was previously dismissed as “driveshaft clunk” due to a lack of lube is a huge win for the NNBS trucks service life. Our 08 Denali suffered from the same symptoms and I just dealt with it.

I will say the tune on the previously sold 08 Denali trans and our current 09 Esky Plat trans is nite and day. The Caddy AWD trans is a slushbox compared to the Denali trans tune.

The info in this thread along with the remedy to the 07-08 trans slip from 1-3 will make life a hell of a lot easier for owners and buyers.

tapatalk://www.cadillacforums.com?channel=share_link_topic&type=xf20_1.2.9&location=topic&fid=204&tid=236374


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[Geotrash]

The info here that was previously dismissed as “driveshaft clunk” due to a lack of lube is a huge win for the NNBS trucks service life. Our 08 Denali suffered from the same symptoms and I just dealt with it.

I will say the tune on the previously sold 08 Denali trans and our current 09 Esky Plat trans is nite and day. The Caddy AWD trans is a slushbox compared to the Denali trans tune.

The info in this thread along with the remedy to the 07-08 trans slip from 1-3 will make life a hell of a lot easier for owners and buyers.

tapatalk://www.cadillacforums.com?channel=share_link_topic&type=xf20_1.2.9&location=topic&fid=204&tid=236374


Sent from my iPhone using Tapatalk Pro

Thanks for the link to the info. Looks like it just goes to the forum board and not a specific post - at least for me.

 

[Stratrider10]

I've had a clunk in my 07 Yukon XL Denali, since I bought it as-new-to-me, and I have finally solved it.

Whenever I was stopped and pushed the accelerator pedal, I would hear/feel a clunk somewhere under my seat. Similarly, whenever I was slowing down, and the transmission downshifted, I would hear/feel the same clunk. I went out of my way to avoid the situations that led to the clunk, so as not to create any potential further damage, until I found out the source of the clunk.

I had thought that the cause of the clunk was the drive shaft slip yoke, as suggested by members of this Forum. As such, I purchased a new nickel plated slip yoke and two new universal joints for that drive shaft, and I had them installed by my local mechanic. Unfortunately, after the installation, the clunk was still there.

Further inspection of the entire drive train and support structure revealed that the bushing assemblies on one of the front differential support mounts were badly worn and required replacement. As such, I had both front differential support mounts and all 4 bushing assemblies replaced. After the installation, the clunk was not longer there.

Our knowledge base for clunk causes and resolutions has been increased.

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So I have already found the 2 arms below your pictures but what exactly are these called as im not finding them anywhere. Thank you and sorry im late to this issue.....

 

[OR VietVet]

@Stratrider10, welcome to the forum and it is explained what they are in the post. Are you saying you cannot find these mounts when looking up by application?

More Information for MOOG RK643171

More Information for MOOG RK643170

 

[Joseph Garcia]

So I have already found the 2 arms below your pictures but what exactly are these called as im not finding them anywhere. Thank you and sorry im late to this issue.....

Front differential support mounts. Be sure that they come with the bushings on both ends of each mount.

 

[Stratrider10]

@Stratrider10, welcome to the forum and it is explained what they are in the post. Are you saying you cannot find these mounts when looking up by application?

More Information for MOOG RK643171

More Information for MOOG RK643170

Okay I was a bit confused on this as I saw the 2 arms and didn't recognize that the bushings were a part of the next photo then..... sorry mate I thought there was a total of 6 bushings instead of JUST the two per arm, like it was another portion. The '07½ yukon denali awd is kinda a new one for me as my previous '07½ tahoe didn't have ½ the issues I'm having with this one. Needs some new front struts and rear shocks but holy cow the cost on those are ridiculous was told you could get some front struts that will cancel out the electronics of the stock but ‍ been working on cars for about 12yrs but nothing with this many bells and whistles. This is my wife's SUV while I drive old reliable '97 K2500 and love the crank windows because they never fail. Thanks for the help guys I really do appreciate your help and time on an old post.

 

[petethepug]

The info in this thread along with the remedy to the 07-08 trans slip from 1-3 will make life a hell of a lot easier for owners and buyers.

tapatalk://www.cadillacforums.com?channel=share_link_topic&type=xf20_1.2.9&location=topic&fid=204&tid=236374

Edit… correct link below

New member and my ESV adventure

Put the OEM Navi disc in and no change. I didn't get to install the OnStar module this afternoon as a rain storm stopped me. Hopefully I can do it tomorrow after work, fingers crossed I get the handsfree working.

www.cadillacforums.com

The moral of the story is purchase the differential bushings already installed in new brackets vs. pressing new bushings into existing brackets. If you don’t you may have an early failure.