2012 Lexus RX450H 3.5L Other · AM12 MEN

The most recent MOT test on 2026-01-28 resulted in a clean pass, marking a return to compliance after two consecutive failures in late 2024 and early 2025. While the overall maintenance trend appears to have stabilised, the presence of two major failures related to the front anti-roll bar ball joint dust covers—both under the same DVSA standard 5.3.4(b)(ii)—indicates a recurring mechanical issue that warrants careful attention. The subsequent passing MOTs suggest the problem may have been addressed, but the history suggests a pattern that could point to either a manufacturing defect in the ball joints or wear-related compromise in the dust covers, which are critical for preventing dirt ingress and subsequent lubrication failure. The offside failure in particular may have been more critical, as anti-roll bar ball joints are load-bearing components that, if compromised, could lead to uneven suspension articulation, excessive wear on suspension components, or even steering instability under load. The vehicle’s recorded mileage of 151,825 miles at a typical annual rate of around 10,845 miles over its 14-year lifespan reflects a moderate but consistent usage profile, which is neither exceptionally light nor overly aggressive for its age. Such mileage is consistent with a mix of daily commuting, occasional long-distance travel, and periods of storage, which can lead to gradual wear on consumables like brake pads, tyres, and suspension components. However, the absence of significant mileage gaps suggests the vehicle has been in regular use, potentially accelerating wear on consumables such as brake linings, which may have reached or neared end-of-life by now, or on suspension elements like bushings and dampers. The lack of higher mileage accumulation—such as 20,000+ miles per year—reduces the likelihood of extreme stress on drivetrain or transmission components, but the anti-roll bar ball joint failures suggest the suspension system has been subjected to cumulative stress, possibly from misalignment, improper servicing, or inherent component fatigue. For the prospective buyer, the most urgent inspection should focus on the front suspension and anti-roll bar assembly. The recurring anti-roll bar ball joint dust cover failures indicate that the ball joints themselves may be worn or degraded internally, leading to lubrication loss and metal-to-metal contact. During a test drive, listen for unusual suspension clunks or rattles, particularly when cornering or over bumps, which could signal loose or binding ball joints. Inspect the anti-roll bars for signs of excessive play or binding, and check for uneven tyre wear patterns that might suggest suspension misalignment. Additionally, visually inspect the ball joint dust covers for cracks or damage, and consider replacing them immediately if they are compromised, as this could prevent further ingress of contaminants. Beyond the suspension, given the vehicle’s age and mileage, a thorough inspection of the brake system is essential. Check for corrosion on brake discs, particularly on the offside front where the MOT failure was noted, and inspect calipers for signs of binding or excessive heat discolouration, which could indicate hydraulic issues or mechanical wear. Brake fluid should be replaced every two years or if it appears dark or contaminated, as this can compromise braking performance. In terms of broader physical checks, the 2012 RX450H’s age and mileage make it a candidate for several time-sensitive inspections. Inspect the tyres for sidewall perishing or cracking, which can occur even with low mileage if the vehicle has been stored for prolonged periods without use. Check the tread depth and look for irregular wear patterns that could indicate alignment or suspension issues. The battery should be tested for capacity and corrosion, as Lexus vehicles of this age can suffer from battery degradation or sulphation, especially if the vehicle has been left unused for extended periods. Fluid levels, including coolant, brake fluid, and differential fluid, should be checked and topped up if necessary, with a reminder to replace brake fluid every two years. The exhaust system should be inspected for leaks or corrosion, particularly around the catalytic converter and exhaust manifolds, as Lexus models of this era can develop rust or wear in these areas. Finally, verify that all service records are up to date, particularly for the timing belt and water pump replacement, which are critical for the RX450H’s engine longevity and should have been serviced around the 100,000-mile mark. If the service book is incomplete, arrange for a professional inspection to ensure no major components have been overlooked.