2025 Toyota Grand Highlander Transmission Problems

Your parked Grand Highlander unexpectedly moved forward about five inches while in Park with the ignition on and air conditioning running, even though no one was in the driver's seat. A passenger felt the vehicle shift forward and heard a sound similar to the engine starting, prompting them to press the ignition button to stop it. This could have caused the vehicle to hit other cars or pedestrians in the parking lot. The issue has not triggered any warning lights and hasn't been diagnosed by a dealership yet.

Your vehicle suddenly lost power while driving on a highway, forcing you to exit immediately. The dealership found damage to the hybrid inverter radiator caused by road debris entering through the front grille, which has large gaps that expose critical components. The repair isn't covered under warranty, and the part is on backorder for weeks to months, leaving your vehicle undriveable during that time.

Your left front axle has been identified as having a defect, and your Toyota dealer has ordered a replacement part. However, the part has been repeatedly delayed — initially promised for February 6, 2026, then pushed to early March, and now expected in late March with no firm guarantee. Because of this safety concern, you don't feel comfortable driving the vehicle, which is affecting your ability to work and earn income. The repair will involve replacing the faulty left front axle assembly.

Your front left axle became defective at under 20,000 miles. While the dealer promised to replace it, you're still waiting for the repair. Driving with a defective axle poses a safety risk and should be addressed as soon as possible. The fix will involve replacing the front left axle assembly.

Your car has experienced violent shaking while stopped, feeling like an earthquake, with no warning lights appearing. The problem has happened before in milder forms and the dealership previously attempted to fix similar stuttering and lurching issues, but they persist and no diagnostic codes are being generated. This suggests the dealer may need to perform a more thorough diagnostic scan or transmission fluid inspection to identify the underlying cause.

Your car makes a clicking or rotational noise from the front drive shafts, especially when accelerating from low speeds while turning. The noise happens frequently during normal driving, and other owners have reported the same issue to your dealer. Although your dealer says they can't reproduce the problem, a similar issue in 2024 Grand Highlanders was resolved by replacing the drive shafts, suggesting the fix may involve replacing one or both front drive shaft assemblies.

Your vehicle occasionally fails to accelerate when you press the gas pedal, particularly when the EV battery is at 3 bars or lower and the vehicle is in Normal mode. The loss of power lasts a few seconds before normal acceleration returns, and no warning lights appear. This creates a safety concern when crossing intersections or entering roundabouts, as your vehicle only coasts instead of accelerating normally. A firmware update has been applied but hasn't resolved the issue.

Your engine is shaking and vibrating when stopped or accelerating from a standstill up to 40 mph. In one instance, the engine shut off completely while experiencing this problem. This issue started around 4,800 miles on your vehicle. The problem likely involves fuel delivery, ignition timing, or engine misfires, which may require diagnostic testing and component replacement or service.

Your transmission often struggles to shift smoothly from first gear, causing harsh, jarring shifts—especially during acceleration or stop-and-go traffic. Sometimes the transmission refuses to shift at all until you pull over, turn the car completely off, and restart it. This unpredictable behavior creates a safety concern when merging or driving in busy conditions. A transmission fluid flush, filter replacement, or transmission software update may be needed to restore smooth shifting.