M256 vs OM606
Side-by-side reliability comparison
Higher reliability score
OM606
BEST
96/100
+16 points over M256
0
/ 100
BUY
M256
Mercedes-Benz
0
/ 100
BEST
OM606
Mercedes-Benz
Specifications
M256
OM606
Brand
Mercedes-Benz
Mercedes-Benz
Verdict
BUY
BEST
Reliability
80
96
Years
2017--present
1993--2001
Displacement
2999 cc
2996 cc
Layout
I6
I6
Type
Petrol Turbo
Diesel
Power
367--435 hp
134--174 hp
Known Issues
2
2
Total Risk Cost
€1,200--€4,000
€280--€700
Character
M256
"MB returns to I6. EQ Boost. Smooth, powerful. Still proving itself."
OM606
"Legendary. 500k+ miles documented. Tunable to 500hp. One of most reliable engines ever."
Issues Comparison
M256 2
● MODERATE
48V ISG starter-generator complexity
○ MINOR
Timing chain (early data building)
OM606 2
○ MINOR
Glow plug failure (only meaningful issue)
○ MINOR
Injection pump seal wear (age-related)