Joining the rear diff club

[Crispy]

Greetings, 2018 X with 15k. Very good info here. Thanks all. Crawled under ours yesterday to see a leaky pinion seal. Happened to be by our dealer so stopped just to check in and ask about it. Service person hadn’t heard anything but advised getting it in. The diff case was clean but slinger had sent it all over the curved body member above the rear. We can’t get in for a while so I wiped it clean and will do my own check again. I will update. C.

 

[FavaBean]

Those who have had issues should provide build dates. It doesn't predict failure, but may provide useful trend data.

 

[BenD]

Those who have had issues should provide build dates. It doesn't predict failure, but may provide useful trend data.

May 2019 Germany, 13k km

 

[ChibiBlackSheep]

Welp... 7 weeks later and I finally got my car back.

 

[BenD]

Welp... 7 weeks later and I finally got my car back.

That’s crazy!! At least it’s done! Hope that will work fine!

 

[ChibiBlackSheep]

That’s crazy!! At least it’s done! Hope that will work fine!

It better have worked! I just resealed my driveway, so all of the diff fluid spots are gone... we'll see if there's anymore.

This parts shortage issue for this car is awful. Took weeks to get the lower control arms in, but at least I had my car during those weeks. Being 7 weeks without this car sucked. Not much on the market has this cargo space, and I didn't realize just how much I use that space until I didn't have it.

 

[Hunter Mike]

Welp... 7 weeks later and I finally got my car back.

It took a few days to get mine, something isn’t right

 

[ChibiBlackSheep]

It took a few days to get mine, something isn’t right

Maybe you got the last one 😀

 

[agaric]

If the diff unit comes from a third party and a problem occurs GM may be running into the situation where a problem part has low availability due to high demand. There may even have been a manufacturing/assembly change needed if that was the cause of the seals failing.

 

[Metatron723]

Hi all! Great info from the group. Just joined the rear differential club. 2018 TourX with 19.5K miles. Dealer order the diff but it is backordered with no projected date. He said it could be 2 days, 2 weeks, or 2 months.

The tech said the car is safe to drive. Anyone have any issues driving theirs with the bad diff?

 

[Voyager989]

The service writer told me not to drive it; but they also told me it'd be 3-4 days for the part and I should have the car back before the end of the week.

 

[ChibiBlackSheep]

Hi all! Great info from the group. Just joined the rear differential club. 2018 TourX with 19.5K miles. Dealer order the diff but it is backordered with no projected date. He said it could be 2 days, 2 weeks, or 2 months.

The tech said the car is safe to drive. Anyone have any issues driving theirs with the bad diff?

I didn't drive it for 7 weeks. If a diff is leaking and groaning, I don't think you should be driving on it at all. At most a couple of days, but they should have you in a rental because you are under warranty.

 

[Voyager989]

Got it back Friday, so a four day turnaround. Diagnosis; "Worn friction discs".

 

[Crispy]

2018 TourX with 15k. Build date 1/2018. Got our car in for an inspection of the leaking pinion seal and they confirmed it. The part came in 2 days later and we have booked a day for the repair.
In my experience, seals fail because the surface they’re around moves too much. Of course they also fail from improper installation, contamination or something else takes them out from the outside.
I will be keeping a close eye on this but I’m wondering what you all think the failure mode is? I have already made it known that I’m tracking other failures and want to be careful to stay within warranty. Thanks, C

 

[bostontourx]

Does anyone have a recording of the noisy diff sound?

Also, where are you seeing leak? Is it easy to spot just sliding under the car?

 

[Crispy]

Does anyone have a recording of the noisy diff sound?

Also, where are you seeing leak? Is it easy to spot just sliding under the car?

Easy to see on our car. The curved body member above the pinion shaft (driveshaft input to diff) was covered with clean shiney oil. Ours wasn’t dripping anywhere but everything within reach of the slinger (the ring that rotates with the pinion shaft outside of the diff case) was lightly coated with oil. I cleaned it off and after one 45 minute trip including some highway, the film was back. C.

 

[94cruiser]

Can someone snap a few pictures describing the different components?

 

[Hunter Mike]

Can someone snap a few pictures describing the different components?

first photo is the pinion shaft as you would look towards the rear of the car. Second is the slinger, third is slinger removed so you can see the seal. The seal fails causing oil to reach the slinger and be thrown on the tunnel and ground.

 

[BenD]

first photo is the pinion shaft as you would look towards the rear of the car. Second is the slinger, third is slinger removed so you can see the seal. The seal fails causing oil to reach the slinger and be thrown on the tunnel and ground.
View attachment 27215
View attachment 27216
View attachment 27214

Is this a magnet?

 

[Hunter Mike]

Is this a magnet?

I would surmise it’s a balancing weight, similar to those used on driveshafts.