Best used luxury SUV under $50k?

Based on the available owner data, the Acura MDX is the only one you can properly evaluate for reliability and value. The BMW X5 and Lexus RX have no owner-reported issues or recommendations in the data, so you cannot make an informed choice between them. For your $50,000 budget, comfort, and reliability priorities, the MDX is the clear pick.

The Acura MDX fits your budget well, with used prices ranging from about $19,000 to $48,000 for 2008-2026 models. Owner data highlights strong mechanical reliability, especially with the 3.5L V6, but warns that transmission failure is common between 180,000-250,000 miles if maintenance is skipped. Fluid changes every 30,000 miles are critical. Timing belt replacement every 105,000 miles is also mandatory, skipping it can destroy the engine. Fuel economy is poor at 16-19 MPG combined, and it requires premium gas. The interior is nice for its era, but infotainment and safety tech are outdated in older models. This SUV suits budget-conscious families who prioritize durability over modern features.

The BMW X5 and Lexus RX have no owner data in the provided records. Without reported issues, maintenance costs, or recommendations, you cannot assess their reliability or long-term value. The Lexus RX price data shows typical used prices from $52,776 to $60,333 for 2025-2026 models, which exceeds your $50,000 budget. The BMW X5 price range starts at $22,398, but no owner feedback exists to guide you on common problems or ownership experience.

For your situation, the Acura MDX offers the best overall value and reliability among these three, but only if you accept its older technology and higher maintenance needs. Stick with a 2018-2020 model year to balance features and reliability, and verify service records for transmission and timing belt work. If you want a more modern interior or better fuel economy, you will need to look at other vehicles with available owner data.