The 1991 BMW M5 is a high-performance, four-door sports sedan from the E34 generation, built for drivers who want classic BMW balance with serious horsepower. Positioned at the top of the 5 Series range, it delivered supercar-level acceleration in a refined executive package. It’s ideal for enthusiasts who value a manual transmission, period-correct analog feel, and long-distance comfort without giving up handling. Today, it sits firmly in modern-classic territory, with values influenced heavily by maintenance history and originality.

- 3.6L inline-six (S38B36) with a factory rating around 310 hp and 266 lb-ft, paired to a 5-speed manual transmission; rear-wheel drive performance with a distinctive high-rev character. - E34 chassis tuning with sport suspension and stronger brakes than the standard 5 Series, offering sharp steering feel and stable high-speed cruising. - Limited-production, hand-assembled M-car heritage, making the 1991 model a collector-friendly year in the early E34 M5 run. - Premium long-haul cabin with supportive sport seats, high-quality materials, and a driver-focused layout typical of BMW’s peak analog era. - Classic “sleeper” styling: understated looks with functional upgrades, appealing to buyers who prefer performance without flashy bodywork.

Searches like “1991 BMW M5 problems,” “1991 BMW M5 reliability,” and “1991 BMW M5 common issues” usually come down to age-related wear, deferred maintenance, and the reality that the S38 is a specialized engine. These cars can be dependable when maintained correctly, but neglected examples get expensive quickly. 1) Timing chain guides and top-end wear: The S38 uses a timing chain, not a belt, but chain guides and tensioner components can wear with age. High-mileage cars (often 120,000–180,000 miles) may also show valve-train noise or top-end wear if oil changes were skipped. A rattly start-up, persistent ticking, or poor compression/leak-down results are red flags. 2) Cooling system weaknesses: Radiators, water pumps, plastic tanks, hoses, and thermostats can fail after decades, and overheating is a serious risk on this engine. Many owners report cooling issues around 80,000–140,000 miles, but age is the bigger factor than mileage. Any history of overheating should be treated cautiously. 3) Oil leaks and gasket seepage: Common leak points include the valve cover gasket, oil pan gasket, timing cover areas, and power steering hoses. Leaks aren’t unusual on a 1991 car, but heavy seepage can foul rubber components, create smoke on the exhaust, and hide bigger maintenance neglect. 4) Suspension and driveline wear: Worn thrust arm bushings, control arms, tie rods, and rear subframe components can cause shimmy under braking, vague steering, or clunks. At higher mileage (100,000+), clutch wear, guibo/flex disc cracking, and driveshaft center support bearing noise are also common complaints.