2018 Tesla Model 3 power train problems

“While my wife was driving, the high-voltage battery failed and the car went into reduced power/limp mode. Tesla later determined that coolant had gotten into the high-voltage battery and caused it to fail. My main concern is that we had no warning that there was a coolant leak or that coolant was getting into the battery. There was no low-coolant warning or anything telling my wife that there was a serious problem developing. By the time the car started giving high-voltage and reduced-power warnings, the damage had already occurred and Tesla said the battery needed to be replaced. What concerns me even more was what happened after Tesla received the car. Tesla removed the battery and quarantined it in the parking lot. They told us in writing that it was removed because of coolant ingress as a safety precaution and that a specialized technician had to determine whether the battery was safe to discharge. During a phone call, a Tesla employee also told me they quarantined it because there was a possibility the battery could explode and they did not want anyone injured or anything damaged if that happened. That was alarming because my wife had just been driving…”

“I am reporting a front suspension failure on my 2018 Tesla Model 3 Dual Motor, that appears relevant to NHTSA Preliminary Evaluation PE26006 and similar to Recall 23V-235. While driving slowly in a parking lot, I heard a clunk and felt the front wheel/steering alignment become slightly skewed. After entering the highway, the vehicle developed severe vibration and became unstable and difficult to control. I exited and stopped as soon as safely possible. While attempting to park it at a curb, during reverse, the suspension entirely collapsed and left front wheel was then severely displaced and the tire was rubbing the wheel well. Tesla inspected the vehicle and confirmed: “The left lateral link was found detached with missing hardware.” Tesla also found the left front halfshaft detached from the drive unit. Tesla replaced the front subframe, both front lower lateral links, both front lower compliance links, the left front halfshaft, and performed an alignment. Total cost was $6,328.96. The failed parts were replaced by Tesla; I do not know whether they remain available for inspection. This failure created a serious risk of loss of vehicle control at highway speed…”

“Description of the Safety Defect:My 2018 Tesla Model 3 AWD suffered an abrupt and catastrophic total loss of mechanical braking power while driving. The brake pedal went completely soft, and the vehicle lost hydraulic pressure.An independent mechanic inspected the undercarriage and confirmed that the factory steel hydraulic brake lines completely rusted through and ruptured, leaking all brake fluid from the system. This vehicle has 142,905 miles and has been operated in regions that use winter road salt.Tesla is aware of this severe corrosion defect under Service Bulletin SB-26-33-001, but they have categorized it as a service bulletin rather than a safety recall. A factory brake line rusting through to total fluid failure is an extreme and immediate safety hazard to occupants and the public. Furthermore, the vehicle simultaneously threw a "Front Motor Disconnected" warning. A federal investigation and mandatory recall are urgently required to ensure Tesla replaces these defective lines for all affected owners before a fatal accident occurs.”

“The front upper control arms on my 2018 Tesla Model 3 have failed multiple times, producing loud clunking, popping, and binding noises during steering. The issue has worsened and poses a serious risk of loss of control while driving. Tesla replaced these parts under goodwill in the past, but the failures have returned. The most recent incident occurred around 03/05/2025 at approximately 106,867 miles. The failure has been confirmed and documented by Tesla Service Centers, and I have multiple invoices showing repeated replacements of the same components. The problem directly affects steering and suspension safety.”

“I just traded in my vehicle for a Tesla from 3rd party dealership on [XXX] A light came on once I reached my home. I called right away before the dealership closed but no one answered. So I took it upon myself to make a service call to Tesla to get my vehicle checked come to find out my vehicle has extensive damages from my unit drive, my subframe and the battery pack is severe punctures and needs to be replaced. Choice Automotive LLC in Honolulu Hawaii didn’t disclose anything to me before purchasing this vehicle. also they didn’t disclose that this vehicle was in a car accident, but they carried on with the sale. I have pictures of what needs to be repaired. Tesla said, I will need $20,000 to repair these damages. So I’m trying to take legal action against Choice Automotive LLC for selling me a vehicle that needs a lot of repair to drive normal again. I need them to pay for these repairs immediately.”

“On March 21, 2025, my Tesla Model 3 Long Range entered "Power Reduction Mode" — a safety feature that limits power to protect the high-voltage battery from overheating or failure. Tesla later diagnosed a coolant leak near the battery area. Their own service advisor stated in writing that the failure was “most likely related” to the battery’s thermal management system — the very system responsible for regulating battery temperature and preventing damage. Despite the connection to the battery protection system and the vehicle being under the 8-year/120,000-mile battery warranty, Tesla has refused to cover the repair. The issue remains unresolved, and I have not picked up or approved any repairs on the vehicle. My concern is that driving the vehicle in this state — or leaving this failure unaddressed — could lead to further battery damage or pose a safety risk. I am requesting that NHTSA evaluate this issue as a potential safety concern, especially as the manufacturer is refusing to repair a system directly linked to high-voltage battery safety.”