Joining the rear diff club

[remmy]

Yeah, that's the primary indicator. Good luck with the process. If they just replace the seal like they did mine, tell them you'll see them again next month.

😂

 

[kbtuba]

So the dealer replaced the rear diff assembly, I don't really have any details beyond that. I had not been looking for leaks, nor had seen any drips or other signs. I had the 'groan' noise, first while turning right, later thru all acceleration, but I can't say that I ever felt a difference in performance. The dealer confirmed that this would be covered under the drivetrain warranty, so I'm just going to keep a eye out for future and hope the whole problem came down to a bad batch of parts.

 

[BenD]

I wonder if this vehicle was originally designed to accept an awd system? I think the driving shaft brackets are too tight and this causes vibration and is also misaligned which causes pressure on the seals and ultimately a seal rupture.

 

[ZB Commodore Owner]

I wonder if this vehicle was originally designed to accept an awd system? I think the driving shaft brackets are too tight and this causes vibration and is also misaligned which causes pressure on the seals and ultimately a seal rupture.

I'm pretty sure it was, there plenty of AWD models with this variant from Opel/Vauxhall. The Opel/Vauxhall model that preceded this also had AWD. There's nothing particularly special or new about it being AWD.

 

[adam728]

Yeah, that's the primary indicator. Good luck with the process. If they just replace the seal like they did mine, tell them you'll see them again next month.

Just got it back. Pinion seal and slinger. We'll see how it lasts.

 

[Kappy]

rear diff leaking again after left seal was replaced a year & 10K miles ago. Back to the dealer. Does anyone know if this is covered under the 6yr/70,000mi powertrain warranty. I'm still within the 4yr bumper to bumper, but wonder about NEXT time. Can't be doing this every 10k miles...........

 

[mike69440]

2018 with 36,200 Miles.

Will get fluids replaced next year. Damn salt!

 

[jdoodle]

rear diff leaking again after left seal was replaced a year & 10K miles ago. Back to the dealer. Does anyone know if this is covered under the 6yr/70,000mi powertrain warranty. I'm still within the 4yr bumper to bumper, but wonder about NEXT time. Can't be doing this every 10k miles...........

The rear diff is covered under the longer powertrain warranty.

 

[Sweden]

The rear diff is covered under the longer powertrain warranty.

 

[Crispy]

Just an update from a Club member. Had the car up today and checked the diff. It’s been 13 months and 9k miles since the pinion seal was replaced. I can’t say the body above the pinion was exactly bone dry but it definitely wasn’t an active leak. I had cleaned this area 8 months ago so I was hoping for chalky dry dirt. When I wiped it clean, there was a sheen to the painted surface. The diff itself was dry as a bone and showed no signs of oil. I’m just going to watch it and keep the warranty in mind. Maybe check the level next summer when I’m under there.

 

[Tdip]

I just found this forum. I have been dealing with a noisy differential on a 2018 TourX since it reached 22,000 miles (I took possession in March 2019). On the first dealer visit, I was told it is "normal". Returned to the dealer again around 50,000 miles and the noise had become even more noticeable upon turning left or right, accelerating, and climbing any grade. This time the dealer acknowledged the problem and changed the "fluids". This did little to solve the problem. I returned to the dealer again last week and they are back to denying the problem and told me the differential is no longer covered under warranty (>70,000 miles). A replacement was quoted at $3500. Clearly, this part is defective and the dealer/GM refuses to accept the responsibility. This is the first GM vehicle I have owned since 1989 and now the last. I remember why I stopped...

 

[garbageguy]

2018 with 36,200 Miles.

Will get fluids replaced next year. Damn salt!

maybe 'they' could've designed-in a slow, small, sustainable 'leak' to keep the surfaces a bit oiled to maybe slow salt attack?

JK - but I swear the old '70 Skylark's various incomplete seals kept that thing alive in the salt for about 30 years,,,

 

[Kappy]

TourX back from dealer for 2nd rear diff leak. This time they replaced the pinion seal & slinger @ 25,300 miles. They had it 3 working days. Last time at 16,200 miles, they replaced the left seal. When questioned, the Service advisor said seals are NOT covered under the powertrain warranty, glad the 18's have 4yr bumper to bumper warranty as ours was 3 years old in October.

 

[saab93driver]

TourX back from dealer for 2nd rear diff leak. This time they replaced the pinion seal & slinger @ 25,300 miles. They had it 3 working days. Last time at 16,200 miles, they replaced the left seal. When questioned, the Service advisor said seals are NOT covered under the powertrain warranty, glad the 18's have 4yr bumper to bumper warranty as ours was 3 years old in October.

You might want to question that with factory. The published warranty information says seals are covered for the transaxle, they don't go on to specifically call out the diff or rear axles on website but somewhere there must be an official document.

 

[remmy]

You might want to question that with factory. The published warranty information says seals are covered for the transaxle, they don't go on to specifically call out the diff or rear axles on website but somewhere there must be an official document.
View attachment 34997

I interpret Naval Aviation instructions and pubs for a living. That blurb covers it and even says what wont be.

 

[steveymars]

So I had about 80K miles on my 2018 Tourx. While performing an oil change I noticed the differential leaking so I replaced the driveshaft input seal with an OE GM part sourced from the dealer. (We totaled the driveshaft in the process but that's a different story). We had some Redline 75/90 laying around so we filled it with that. Within a few hundred miles it was growling, especially turning right. Then it just felt all kinds of wrong. The dealer wanted $ 2800 for a replacement diff. We drained and refilled it with the correct LS fluid which accomplished nothing.

Lastly, I sourced a diff from a junk yard with low miles and had it shipped to Austin for $ 375 total. My mechanic installed it for $ 475 and now I'm back on the road. I really love everything about my Tourx except the build quality of the drive train. I had an oil pan leak and exhaust leak repaired under warranty and now this. I haven't heard of a differential going out on a vanilla civilian car ever. If your car still has warranty I would pay careful attention to when it expires and have it thoroughly inspected and repaired be it runs out.

 

[danzig997]

So I had about 80K miles on my 2018 Tourx. While performing an oil change I noticed the differential leaking so I replaced the driveshaft input seal with an OE GM part sourced from the dealer. (We totaled the driveshaft in the process but that's a different story). We had some Redline 75/90 laying around so we filled it with that. Within a few hundred miles it was growling, especially turning right. Then it just felt all kinds of wrong. The dealer wanted $ 2800 for a replacement diff. We drained and refilled it with the correct LS fluid which accomplished nothing.

Lastly, I sourced a diff from a junk yard with low miles and had it shipped to Austin for $ 375 total. My mechanic installed it for $ 475 and now I'm back on the road. I really love everything about my Tourx except the build quality of the drive train. I had an oil pan leak and exhaust leak repaired under warranty and now this. I haven't heard of a differential going out on a vanilla civilian car ever. If your car still has warranty I would pay careful attention to when it expires and have it thoroughly inspected and repaired be it runs out.

I wonder if the rear diff assembly is specific for Tourx or it is interchangeable with other GM models. The Tourx is using GKN Twinster differential by UK-based GKN Automotive Limited.

2019 Regal TourX GKN Twinster fluid change.

https://bobistheoilguy.com/forums/threads/2019-regal-tourx-gkn-twinster-fluid-change.316254/

 

[remmy]

I wonder if the rear diff assembly is specific for Tourx or it is interchangeable with other GM models. The Tourx is using GKN Twinster differential by UK-based GKN Automotive Limited.

2019 Regal TourX GKN Twinster fluid change.

https://bobistheoilguy.com/forums/threads/2019-regal-tourx-gkn-twinster-fluid-change.316254/

From what I understand, it’s the same diff from a Focus RS. But I’m not aware of RS owners having any issues like ours.

 

[danzig997]

From what I understand, it’s the same diff from a Focus RS. But I’m not aware of RS owners having any issues like ours.

I found some additional info that the TourX uses the GKN Twinster rear differential, same as a few other cars like the Ford Focus RS, Land Rover Discovery, Range Rover Evoq. GKN is headquartered in England and right now, getting things shipped out of England is apparently very problematic.

 

[Crispy]

Update- It’s been almost two years and 21k miles since our pinion seal was replaced. I was under there yesterday and no sign of oil. Not even damp. C.