Why does the Lexus UX shake in D gear?

[VonMolly]

The main reasons for the Lexus UX shaking in D gear are as follows: 1. Carbon deposits. If the engine has carbon deposit issues, it may cause the engine to shake when driving in gear. 2. Abnormal transmission oil pressure. In vehicles that have not had their transmission oil changed or their oil circuit plate cleaned for a long time, the automatic transmission's oil pressure continuously fluctuates in D gear, leading to excessive oil pressure and abnormal transmission shaking. 3. Damage to the rubber of the transmission mount. 4. Degraded transmission oil or dirty oil circuit. If the vehicle has not had its oil circuit plate cleaned or transmission oil changed for a long time, it is advisable to change the transmission oil and clean the oil circuit plate.

[DiAdriel]

I've been pondering this D-gear shaking issue with my UX for quite a while. The phenomenon is most noticeable at low speeds or when stationary – like when waiting at a red light with the foot brake engaged in D-gear, you can feel the steering wheel buzzing with vibration. The key is observing the pattern: if it shakes violently when stationary with brakes applied but improves when releasing the brake to start moving, it's likely due to aged engine mount bushings. The hybrid nature of this vehicle complicates matters – the instant torque changes during engine start-stop can overwhelm the mounts, causing vibrations. Last time, I specifically tested shifting to N-gear and confirmed the shaking disappeared, pinpointing it as a powertrain component issue. Also check for play in the CV joint and remember that excessive tire imbalance can amplify the shaking sensation. Recommend pulling diagnostic trouble codes promptly to prevent minor issues from escalating into major repairs.

[Fitzgerald]

Just helped a friend deal with a similar case last week. For the Lexus UX shaking in D gear, focus on three main areas. First, the engine mounts—rubber components harden and become brittle over time, losing their damping effect, especially the hydraulic mount on the right side, which is prone to failure. Second, the abruptness when the auto start-stop system engages; try turning it off to see if there's improvement. Third, the power coupling process in the hybrid system, where the transition from electric motor to engine drive isn't smooth. A simple self-test: after the car is fully warmed up, press the brake firmly and shift to D gear, observing if the tachometer needle fluctuates frequently. Our shop's tests show that UX models over 80,000 km usually need upgraded brackets, as the factory parts have improved rubber formulations.

[DeChase]

I encountered the same issue last year! The dealership diagnosed it as abnormal operation of the torque converter lock-up clutch. In Lexus hybrid systems, the torque converter should maintain a flexible connection when coming to a stop in D gear, but under certain conditions it may erroneously lock up, causing body vibration. Here's a little-known fact: Lexus issued a technical bulletin for the UX hybrid, recommending an ECU software update to improve low-speed vibration. Additionally, it's important to check the transmission fluid condition, as deteriorated CVT fluid in hybrid models can exacerbate vibration transmission. Last time, the technician taught me a trick: after starting the engine, switch to sport mode and engage D gear - if the vibration significantly reduces, it's likely a torque converter control logic issue.

[MacCole]

Excessive vibration in hybrid vehicles when in D gear should primarily raise suspicion about the energy recovery system. When the brakes are applied to a stop, the generator reversely drags the engine, causing additional vibrations. Many Lexus UX owners in the group have reported this issue, and we've summarized several key points: 1. Vibration worsens when the air conditioning compressor is activated. 2. Vibration reduces when the battery is fully charged. 3. Upgrading to the 2022 or later vehicle firmware is effective. It's recommended to turn off the air conditioning and seat ventilation during testing to see if the vibration disappears. Also, don't overlook tire factors; tire pressure exceeding 2.5 bar can amplify engine vibration transmission, and reducing front tire pressure to 2.3 bar works wonders. Recheck the torque of chassis screws as well; last time, a loose subframe bolt caused resonance.

[DelFinn]

The D-gear vibration actually involves the overall vehicle matching issue. During last week's technical training, Lexus engineers emphasized three key points for the UX's engine mounting system: checking for silicone oil leakage in hydraulic mounts, measuring the actuator resistance value of electronically controlled active mounts (if equipped), and inspecting the condition of exhaust pipe rubber hangers. An important detail: if steering wheel vibration occurs when stationary in D-gear but immediately stabilizes when shifted to P-gear, tire dynamic balance issues can be basically ruled out. It's recommended to set the air conditioning to maximum temperature and highest fan speed to force the engine to operate - if vibration reduces under these conditions, it indicates insufficient vibration suppression in the hybrid system's pure electric mode. We've handled similar cases where replacing with improved half-shafts with damping blocks showed significant improvement.