OM668 vs OM606

Side-by-side reliability comparison

Higher reliability score
OM606 BEST 96/100
+38 points over OM668
0 / 100
CAUTION OM668 Mercedes-Benz
0 / 100
BEST OM606 Mercedes-Benz

Specifications

OM668
OM606
Brand
Mercedes-Benz
Mercedes-Benz
Verdict
CAUTION
BEST
Reliability
58
96
Years
1998--2004
1993--2001
Displacement
1689 cc
2996 cc
Layout
I4
I6
Type
Diesel
Diesel
Power
75--95 hp
134--174 hp
Known Issues
2
2
Total Risk Cost
€800--€2,000
€280--€700

Character

OM668

"W168 A-Class. Same era as M166 petrol. Injector issues. Head gasket concerns. Turbo failure on higher-output version. Not Mercedes' best diesel. Better alternatives exist."

OM606

"Legendary. 500k+ miles documented. Tunable to 500hp. One of most reliable engines ever."

Issues Comparison

OM668 2

▲ HIGH
Head gasket failure €500--€1,200 80,000 km--150,000 km
● MODERATE
Injector failure €300--€800 80,000 km--150,000 km

OM606 2

○ MINOR
Glow plug failure (only meaningful issue) €80--€200 80,000 km--∞
○ MINOR
Injection pump seal wear (age-related) €200--€500 200,000 km--∞

Models

OM668 2

A-Class W168 1998--2004 A-Class W168 1998--2004

OM606 2

300D W124 1993--1997 Sedan E 300D W210 1995--2003 Sedan
Full OM668 Report Full OM606 Report