The E39 M5 with its S62 V8 is a legendary sports sedan, but it demands serious respect and maintenance dollars. The engine itself is fairly robust if maintained, but the VANOS system, rod bearings, and that troublesome SMG transmission are where owners get hurt financially.
Rod Bearing Failure (S62 V8)
Occasional · high severityTypical onset: 80,000-140,000 mi
Symptoms: Metallic knocking on cold start that may disappear when warm, Metal shavings in oil during analysis, Catastrophic engine failure if ignored—connecting rod punches through block
Fix: Preventive replacement requires engine-out, 18-22 labor hours. If it spins a bearing, you're looking at full engine rebuild or replacement. This is THE existential threat on S62 engines.
Estimated cost: $6,000-9,000 preventive; $15,000-25,000 if grenaded
VANOS System Wear (Variable Valve Timing)
Common · medium severityTypical onset: 60,000-100,000 mi
Symptoms: Cold-start rattle for 2-3 seconds (sounds like marbles in a can), Rough idle and hesitation, Check engine light with cam position codes (P1519, P1520)
Fix: Rebuild both VANOS units with updated seals and pistons. 8-10 hours labor. Often done alongside valve cover gaskets since you're in there.
Estimated cost: $2,500-4,000
SMG Transmission Pump Failure
Common · high severityTypical onset: 70,000-110,000 mi
Symptoms: Grinding/whining noise from transmission tunnel, Fluid leaks at pump (located under car, forward of transmission), Gear selection errors, failure to shift, stuck in gear, Eventually total loss of hydraulic pressure—car won't move
Fix: Replace SMG hydraulic pump and accumulator. 6-8 hours labor. Often the relay fails first (cheaper), but pump failure is inevitable. This is not a question of IF but WHEN.
Estimated cost: $2,000-3,500
Timing Chain Guide Wear
Occasional · high severityTypical onset: 100,000-150,000 mi
Symptoms: Rattling from front of engine on startup, Pieces of plastic guide found in oil pan during changes, Can lead to jumped timing or catastrophic engine damage if chain slips
Fix: Replace timing chain, guides, tensioners, and seals. Engine does NOT need to come out but it's a 20-25 hour job. Do NOT defer this if rattling is present.
Estimated cost: $4,500-7,000
Rear Subframe Mounts Tearing
Common · medium severityTypical onset: 80,000-120,000 mi
Symptoms: Clunking over bumps from rear, Wandering rear end under hard acceleration or braking, Visible cracks in sheet metal around subframe mount points
Fix: Requires subframe reinforcement plates welded in, then new mounts. 8-12 hours labor depending on how bad the damage is. This is an E39 chassis-wide issue, worse on M5 due to power and weight.
Estimated cost: $1,500-3,000
Transmission Output Shaft Bearing Failure (SMG)
Occasional · medium severityTypical onset: 90,000-130,000 mi
Symptoms: Whining or growling noise in all gears that changes with speed, Noise persists in neutral with clutch engaged, Metal debris in transmission fluid
Fix: Transmission must come out. Replace output shaft bearing and seals, inspect for collateral damage. 12-16 hours labor. Often discovered during SMG pump replacement.
Estimated cost: $3,000-5,000
Cooling System Failures (Expansion Tank, Water Pump, Thermostat)
Common · medium severityTypical onset: 60,000-100,000 mi
Symptoms: Coolant weeping from expansion tank cracks, Overheating in traffic or on track, Coolant temperature fluctuations, Water pump shaft bearing noise (squealing)
Fix: Replace expansion tank, water pump, thermostat, and all hoses as a package. 4-6 hours labor. Plastic components age-out regardless of mileage. S62 does NOT tolerate overheating.
Estimated cost: $1,200-2,000
Buy one only if you have a $10k repair fund and a trusted BMW specialist on speed-dial—these are expensive to own but transcendent to drive when sorted.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.