2019 Kia Stinger GT RWD with 3 rear diff failures

[JennaD]

Hi all, I have a 2019 Kia Stinger GT RWD that has been in the shop 3 times all with rear differential failure. The original diff failed in June 2023. It has currently been in the shop since December. Kia did a thorough inspection of my car to make sure I was not abusing it. Now they have a technical specialist trying to figure out what is causing it. They think it is the oil and they use Valvoline with the limited slip additive. Another stinger came in in December with the same issue, they replaced her differential and in one month it was toast.
Is this an oil issue? Does anyone else use Valvoline in a different vehicle as their gear oil? Did they change the fluid after all of the issues with Covid and getting supplies? Just trying to figure out what’s happening here.

 

[wpod]

I doubt it is the oil.

 

[JavierH19]

Have a friend that went over 380k on his diff without ever changing the gear oil in his old ford that he bought new and it never made a sound or had an issue. It's a quality issue. Do yourself a favor and lemon law it because even if it'll still be under warranty they'll just surmise you really are abusing it since they're getting suspicious and with that cheap excuse even corporate will struggle to side with you after they stop warrantying you after the 4th diff. Given that you're on you're 3rd and they've failed to fix the issue get a lemon law lawyer since they can get you a 100% refund. Don't waste time on a different gear oil, spend that time with a lemon law lawyer instead.

 

[3783-KC1]

Well, what is specifically failing in the diff? Are the clutches wearing out or are the gears being stripped? 2 cents says that this is a mfg. issue with the diffs. Curious to the mileage though. I use Valvoline 75w140 in the 04' with limited slip additives and it is fine. However, that is a conventional diff designed in late 80s-early 90s. Don't how it would fair with the limited slip diff in the Kia.

 

[BMWTurboDzl]

Hi all, I have a 2019 Kia Stinger GT RWD that has been in the shop 3 times all with rear differential failure. The original diff failed in June 2023. It has currently been in the shop since December. Kia did a thorough inspection of my car to make sure I was not abusing it. Now they have a technical specialist trying to figure out what is causing it. They think it is the oil and they use Valvoline with the limited slip additive. Another stinger came in in December with the same issue, they replaced her differential and in one month it was toast.
Is this an oil issue? Does anyone else use Valvoline in a different vehicle as their gear oil? Did they change the fluid after all of the issues with Covid and getting supplies? Just trying to figure out what’s happening here.

Metallurgy.

 

[KGMtech]

This will not be resolved without full investigation by experts, so it's not going to happen. Lemon Law time.

 

[zzyzzx]

So their differentials are as bad as their engines.

 

[FowVay]

The internet is filled with horror stories of bad differentials. Many enthusiasts have resolved many of the issues with limited slip additives in the oil. Could Hyundai/Kia be foolish enough to install LSD's with no friction modifier or inadequate supplemental additive? I think that's a possibility.

 

[oldcodger]

Agree with others. Without knowing the type or mode type of failure nobody can give good advice, other than lemon law.

 

[I<3oil]

Got Valvoline flexpouch in my Silverado in front and rear diffs right now. Been in for 12k miles and 2 years so far, no issues.

 

[nascarnation]

Lube additives can have a big influence on limited slip but don't fix undersized components or bad quality. No way it takes > two months to analyze this, they're just trying to stall on you. I'd be pushing the issue up the corporate ladder.

 

[Pew]

 

[SHOZ]

I have a limited slip Torsen in my Gen Coupe. 140k miles with oil changes about every 50k. Usually Redline but last time had to use some Total that Rock Auto sent by mistake. GL5 only. Never an issue.

 

[JennaD]

Have a friend that went over 380k on his diff without ever changing the gear oil in his old ford that he bought new and it never made a sound or had an issue. It's a quality issue. Do yourself a favor and lemon law it because even if it'll still be under warranty they'll just surmise you really are abusing it since they're getting suspicious and with that cheap excuse even corporate will struggle to side with you after they stop warrantying you after the 4th diff. Given that you're on you're 3rd and they've failed to fix the issue get a lemon law lawyer since they can get you a 100% refund. Don't waste time on a different gear oil, spend that time with a lemon law lawyer instead.

I did!

 

[JennaD]

Have a friend that went over 380k on his diff without ever changing the gear oil in his old ford that he bought new and it never made a sound or had an issue. It's a quality issue. Do yourself a favor and lemon law it because even if it'll still be under warranty they'll just surmise you really are abusing it since they're getting suspicious and with that cheap excuse even corporate will struggle to side with you after they stop warrantying you after the 4th diff. Given that you're on you're 3rd and they've failed to fix the issue get a lemon law lawyer since they can get you a 100% refund. Don't waste time on a different gear oil, spend that time with a lemon law lawyer instead.

Well, what is specifically failing in the diff? Are the clutches wearing out or are the gears being stripped? 2 cents says that this is a mfg. issue with the diffs. Curious to the mileage though. I use Valvoline 75w140 in the 04' with limited slip additives and it is fine. However, that is a conventional diff designed in late 80s-early 90s. Don't how it would fair with the limited slip diff in the Kia.

Don’t know other than the fluid is black, thin and watery and has metal shavings. They changed out the axles on the second diff. Obviously didn’t fix it. So now they are testing the oil.

 

[twX]

They think it is the oil and they use Valvoline with the limited slip additive. Another stinger came in in December with the same issue, they replaced her differential and in one month it was toast.

If this is not a common problem with these cars, but is a common problem at this dealership, maybe the issue is with their oil. The only Valvoline oil I see with LSD additive is a 75W-85 GL-5, which is what your car specs. The cheaper semi-synthetic is a GL-4 with no LSD additive. Maybe they were trying to save a few bucks.

It has currently been in the shop since December.

I wouldn't be happy with a dealership keeping my car for over 2 months for a simple diff replacement. I'd tell them to just replace it and try different fluid.

Walk into the dealership dressed like this guy so they get the message:

 

[edyvw]

Hi all, I have a 2019 Kia Stinger GT RWD that has been in the shop 3 times all with rear differential failure. The original diff failed in June 2023. It has currently been in the shop since December. Kia did a thorough inspection of my car to make sure I was not abusing it. Now they have a technical specialist trying to figure out what is causing it. They think it is the oil and they use Valvoline with the limited slip additive. Another stinger came in in December with the same issue, they replaced her differential and in one month it was toast.
Is this an oil issue? Does anyone else use Valvoline in a different vehicle as their gear oil? Did they change the fluid after all of the issues with Covid and getting supplies? Just trying to figure out what’s happening here.

Stinger? GT? Abuse? isn't that the point of the vehicle? BMW will prepare your car to go to track it.
I would say it is KIA issue.

 

[Mainia]

Hi all, I have a 2019 Kia Stinger GT RWD that has been in the shop 3 times all with rear differential failure. The original diff failed in June 2023. It has currently been in the shop since December. Kia did a thorough inspection of my car to make sure I was not abusing it. Now they have a technical specialist trying to figure out what is causing it. They think it is the oil and they use Valvoline with the limited slip additive. Another stinger came in in December with the same issue, they replaced her differential and in one month it was toast.
Is this an oil issue? Does anyone else use Valvoline in a different vehicle as their gear oil? Did they change the fluid after all of the issues with Covid and getting supplies? Just trying to figure out what’s happening here.

First off, the FIRST place you should be is not on this site, but on any and all sites pertaining to "tuned" or "highly modified" Kia Stingers. There are people there running 400hp to 800 hp in their Kia Stingers that don't trash 3 differentials in your time frame. Those kind of sites are where your questions can be answered. Remember, if you own a Hyundai or Kia, YOU automatically have to treat your whole car as a "rough service" car no matter if you drive like a grandpa or beat the piss out of it. That means also you don't take advice from Hyundai or Kia on when you should change any of the oil on any part of the car unless it at the "rough service " levels or even sooner then rough service" intervals. When you do get your new diff, find out what oil the top guys on the high performance sites suggest and dump your new diffs oil at 800 miles, then again at 4,000 miles and again at 9,000 miles with the oil that is the consensus of the top posters on that Kia Stinger high performance site. Hyundai/Kia always seem to use the cheapest and WRONG choice for their metallurgy choice. (they choose softer metals as their default choice). Do not listen to Kia, as there is a very very high chance you will be getting advice from someone that hasn't a clue what they are talking about, even if that person is a service manager. Take the advice more from the high performance Kia Stinger community.

 

[JennaD]

If this is not a common problem with these cars, but is a common problem at this dealership, maybe the issue is with their oil. The only Valvoline oil I see with LSD additive is a 75W-85 GL-5, which is what your car specs. The cheaper semi-synthetic is a GL-4 with no LSD additive. Maybe they were trying to save a few bucks.


I wouldn't be happy with a dealership keeping my car for over 2 months for a simple diff replacement. I'd tell them to just replace it and try different fluid.

Walk into the dealership dressed like this guy so they get the message:

View attachment 205864

they are using the correct fluid. That’s why I wondered why there isnt a nationwide issue if it was the oil! I guess that’s why I was posting to see if anyone else has had issues with this same fluid.

Stinger? GT? Abuse? isn't that the point of the vehicle? BMW will prepare your car to go to track it.
I would say it is KIA issue.

 

[edyvw]

they are using the correct fluid. That’s why I wondered why there isnt a nationwide issue if it was the oil! I guess that’s why I was posting to see if anyone else has had issues with this same fluid.

Valvoline gear oil is really good stuff. Culprit is elsewhere. Either quality of part or installation.