6.2L GM vs. 6.6L Duramax

From Detroit To Duramax


The 6.2L GM diesel was designed and released as a fuel saver rather than a work horse. At the time of it's release, a big block gasser would out pull the 6.2L by a long shot. But a big block gasser was not capable of 20+ mpg, quite an achievement for any pickup of the 80's. The 6.2L was engineered to be an economical alternative to the gas guzzling V-8's of the era. Enter the 6.6L Duramax, an engine designed by a joint venture between Isuzu and General Motors. The first Duramax was released in 2001, and it signaled GM's decision to get serious about the diesel pickup category. The Duramax is far more competitive than any previous diesel engine used in GM trucks. The 2011 Duramax is rated at a whopping 765 lb-ft of torque, a far cry from the 240 lb-ft that the 6.2L was rated at.



1982 6.2L GM Diesel

2011 6.6L Duramax LML


6.2L GM V-8 diesel (Detroit Diesel)

6.6L Duramax LML V-8 (Isuzu + GM)

Years of Operation:

1982 - 1993

2011 model year - current


6.2L, 379 cubic inches

6.6L, 403 cubic inches


Naturally aspirated

Turbocharged & intercooled (VGT)

Block/Head Material:

cast iron/cast iron

Cast iron/aluminum


130 hp @ 3,600 rpm (1982)

397 hp @ 3,000 rpm (2011)


240 lb-ft @ 2,000 rpm (1982)

765 lb-ft @ 1,600 rpm (2011)