Summary of Key Points
Tesla China, which launched the six-seater Long Wheelbase Model Y L just over a year ago, has recently faced a surge in complaints from owners about the issue of the "rear end sinking." Numerous vehicles, after traveling thousands to tens of thousands of kilometers, have experienced a reduction in the gap between the rear wheels and the wheel arches from being able to fit four fingers when the car was new to only two to three fingers. This issue is accompanied by other problems such as stiffer shock absorbers, increased susceptibility to bottoming out when going over bumps, body shaking, and abnormal wear on the inner sides of the rear wheels. Some owners have even been involved in accidents on highways during rainy weather. Tesla's current solution is to privately replace the springs in some vehicles with what they call "improved springs," but many owners have experienced the problem recurring just a few months after the replacement. Tesla has not disclosed the cause of the fault, the criteria for determining whether a vehicle needs to be replaced, or officially responded to concerns about recalls, which has led to widespread dissatisfaction among owners. In the first seven months of 2026, 36,000 units of this model were sold in China, and the scope of the issue continues to expand.
---
Detailed Analysis
1. The "rear end sinking" is not a minor issue; it's essentially the "mattress springs" that support the car's body collapsing
Many people think of "rear end sinking" as a minor flaw, but it's easier to understand with a common analogy: the springs in a mattress are supposed to be elastic so that you don't sink into it when you lie down. Over time, the springs lose their elasticity, causing the mattress to sink. The coil springs in a car's suspension serve the same purpose, maintaining the proper distance between the rear wheels and the body. However, in this case, the springs have undergone irreversible permanent deformation and cannot return to their original shape, causing the rear end to sink. This is not a temporary issue caused by heavy loads; even when the car is unloaded, the height cannot return to its original level, posing three serious safety risks:
- The spring's cushioning capacity is gone, so the car hits bumps and potholes with excessive force, potentially damaging the chassis.
- The misalignment of the body causes the rear wheels to scrape against the ground, rapidly wearing down the inner sides of the tires. After 30,000 kilometers, the tires may reach a critical state of wear, leading to poor grip and increased risk of skidding on highways in the rain.
- In severe cases, the car may deviate from its intended path, requiring constant steering adjustments, which is both exhausting and dangerous.
2. Tesla's approach to the issue is clearly attempts to gloss over the problem
Based on customer feedback, Tesla has not intended to address the issue openly from the beginning, preferring to handle it behind the scenes:
- The criteria for determining whether a spring needs to be replaced are kept secret. Tesla has changed the stated height requirements multiple times and refused to share the actual measurement data with customers.
- The so-called "improved springs" have not solved the problem; many owners have experienced the issue again after the replacement. Some were even assured by sales staff at the time of purchase that the new springs would prevent sinking, but after 30,000 kilometers, the gap between the wheel arches and tires was still too small. Tesla only performed a "stress relief" procedure on the springs, which is a superficial fix rather than a thorough solution.
3. The fault is likely due to Tesla's design choices and cost-cutting
Two chassis engineers have suggested that this is not a quality issue with a specific batch of springs but rather a result of Tesla's design flaws. The six-seater Model Y L has additional seats, which means the rear axle has to support more weight, including that of two adults and luggage. Tesla may have simply reused springs from the older five-seater Model Y, which were not designed for such additional load. This misuse of components will inevitably lead to problems.
4. Tesla's refusal to recall the vehicles is strategically calculated
There are several reasons why Tesla is avoiding a recall:
- There is ambiguity in the regulations: while national standards specify that the permanent deformation of springs must not exceed 0.3% when tested individually, there are no clear guidelines for how much the car's height can decrease after being installed on the vehicle. Tesla uses this loophole to argue that its cars still fall within the acceptable range.
- A recall would be costly, with each vehicle requiring replacement of springs, alignment, and compensation for damaged tires, totaling millions of yuan. It would also damage Tesla's reputation for quality, which is crucial in the highly competitive Chinese new energy market.
- The issue has not yet reached the point where regulators would intervene. By delaying a response, Tesla hopes that some owners will settle for compensation on their own, and once a new, redesigned batch of springs is produced, the issue may be forgotten.
5. Consumers affected by this issue should not remain silent
More than 300 owners have formed a group to seek compensation. If you are one of them, do not be deceived by Tesla's internal standards. Keep all evidence, such as photos of the wheel arch gaps, repair orders, communication with customer service, and videos of tire wear. If customer service refuses to replace the springs according to the standards, contact the 12315 hotline or the National Market Supervision Administration's defect product recall platform. The more complaints there are, the greater the chance of regulatory intervention. If the wear on the rear wheels is severe, do not drive on highways; replace the tires immediately for safety.