Autoblog and Yahoo may earn commission from links in this article.Shopping for a used luxury SUV from 2017 puts two of the segment's heaviest hitters on the table. Both the RX 350 and the MDX carry strong brand reputations, seat their occupants in quiet, well-appointed cabins, and sticker within a few hundred dollars of each other. But reliability has always been the dividing line between these two, and the gap widens once you dig into real-world owner data, recall histories, and the MDX's well-documented transmission headaches. If you are spending your money on a used luxury SUV, here is which one is less likely to send you back to the service department.2017 Lexus RX 350How the reliability scores compareFew vehicles in any segment match the RX 350's dependability record. Its reliability ratings average 4.0 out 5.0 ranking it third out of 14 luxury midsize SUVs. Average annual repair costs sit around $550, well below the $807 luxury midsize SUV average, and the severity of those repairs trends low. Simply put, the RX 350 is one of the safest bets in the luxury SUV market.2017 Lexus RX 350By comparison, the MDX also earns solid marks on paper also with a 4.0 out of 5.0 reliability rating. It's more reliable than the average 2017 vehicle. On average, its and reliability score of 83 out of 100 trails the RX 350 by just a single point. Average annual repair costs come in at $571, still reasonable for the class. On the surface, these two look neck-and-neck. But the numbers do not tell the full story.2017 Acura MDXDrew PhillipsRecalls and common complaintsJust three NHTSA recalls have been issued for the 2017 RX 350, a remarkably clean record for a vehicle now approaching a decade on the road. One recall addresses an improperly machined brake booster vacuum pump that could cause a sudden loss of braking assist, while two others cover in-tank fuel pump failures that could stall the engine. Owners have filed roughly 49 complaints total, and the most commonly reported issues, including interior door handle breakage and a water pump coolant leak that may appear around 90,000 to 150,000 miles, are manageable and relatively inexpensive to fix. Nothing on the RX 350's complaint sheet suggests a systemic design flaw.2017 Lexus RX 350AdvertisementAdvertisementSeven NHTSA recalls tell a busier story for the MDX. A fuel pump failure recall mirrors the one affecting the RX 350, and a tailgate lid lighting recall addresses moisture intrusion that can knock out taillights and license plate lights. Beyond the official recalls, the real noise comes from owner complaints about the ZF nine-speed automatic transmission, which debuted in the MDX for 2016 and carried its problems into 2017 unchanged. Owners describe jerky shifts between first and second gear, hesitation during acceleration, lurching from a stop, and in the worst cases, complete transmission failure at higher mileage. Multiple service bulletins were issued to address transmission warmer leaks that could allow engine coolant and transmission fluid to mix, a recipe for permanent damage to both components. Some reliability guides specifically list 2017 as a year to avoid for the MDX because of these recurring powertrain issues.2017 Acura MDXDrew PhillipsLong-term durability and repair costsLongevity is one of the RX 350's strongest selling points. Built on Toyota underpinnings with a proven 3.5-liter V6 and a conventional six-speed automatic, the 2017 model relies on a powertrain combination that has been refined over multiple generations. Owners routinely report reaching well past 200,000 miles with nothing more than scheduled maintenance, and one reliability site pegs the probability of a major repair at just 8%, half the average for the broader luxury segment. Annual maintenance costs around $550 also undercut what you would spend on most German competitors by a significant margin.2017 Lexus RX 350Living with the MDX long-term requires more attention and, potentially, more money. Independent specialists recommend changing the nine-speed transmission fluid every 30,000 miles using Honda DW-1 ATF, regardless of what the onboard maintenance minder suggests, because the system tends to call for service too late. Owners who follow that advice report significantly smoother shifting. For those who did not, repair costs for a full transmission replacement can exceed $4,000. Beyond the transmission, the MDX is a fundamentally solid vehicle with a capable 3.5-liter V6 and a well-built interior, but the powertrain question mark hangs over every used example. Finding a well-maintained unit with documented fluid changes is the key to a happy ownership experience.2017 Acura MDXAcuraThe bottom lineBoth of these luxury SUVs earn above-average reliability marks for 2017, but the margin between them matters. With just three recalls, rock-bottom repair costs, and a powertrain that simply refuses to cause problems, the RX 350 is the clear winner for anyone who prioritizes long-term dependability. It is the kind of vehicle you buy, maintain on schedule, and forget about. However, picking the MDX is not unreasonable, especially if you value its third row, sportier driving dynamics, and lower used prices.AdvertisementAdvertisementThis story was originally published by Autoblog on Jun 12, 2026, where it first appeared in the Car Buying section. Add Autoblog as a Preferred Source by clicking here.
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