Ford New Holland 6.6L, 7.8L Diesel Specs

Ford Brazilian 6.6L & 7.8L I-6 Diesel Specs, History, & Information

The Ford 6.6L/7.8L diesels found in Ford medium duty applications is an adaptation of the naturally aspirated engines engineered in the 1960's by New Holland Machine Company. Ford would utilize a turbocharged version the 6.6L and 7.8L in various medium duty applications, including Ford B-Series buses, after their acquisition of New Holland. The engine's are officially the Ford-New Holland 6.6L and Ford-New Holland 7.8L. They are popularly known as the Ford "Brazilian" diesels as they were produced at New Holland manufacturing sites in Brazil. Reception of both inline 6 cylinder diesels was favorable for Ford and the engines have broadly earned praise for their durability and dependability, albeit somewhat underpowered.

The 6.6L was available with a maximum 170 horsepower and 402 lb-ft of torque while the 7.8L could be ordered with a respectable 240 horsepower and 606 lb-ft of torque. 6.6L engines featured a square bore-to-stroke ratio while the larger 7.8L utilized the same bore but a longer stroke. The Brazilian Fords are far from powerhouses and will win you no races. However, many will argue that they are respectable engines that performed the tasks they were designed for while ranking competitively in the longevity and reliability departments.

In more recent times, the engines have been frequently confused with the 6.6L and 7.8L Duramax diesels designed by Isuzu. There is absolutely no relationship between Isuzu's 6.6L V-8 and 7.8L I-6 and either Ford-New Holland diesels save for the nominal displacement similarities. Different bore diameters, different stroke lengths, yet coincidently similar displacements. The engine series was abandoned following the 1994 model year, being replaced by more powerful (and technologically advanced) engine options. It competed with Cummins, Caterpillar, and Detroit diesel engines, all of which were also offered in Ford medium duty applications during this period.

Ford New Holland 6.6L, 7.8L Brazilian Diesel Specs

  Ford New Holland 6.6L Diesel Ford New Holland 7.8L Diesel
Manufacturer Ford-New Holland
Applications 1985 - 1994 Ford medium duty chassis including B series buses, F-600, F-800, F-900, L-8000
Configuration Inline 6 cylinder (I-6)
Type 4 cycle turbodiesel, sleeveless
Firing Order 1 - 5 - 3 - 6- 2 - 4
Idle Speed (hot) 700 - 750 rpm
Displacement 401 cid, 6.6 liters 473 cid, 7.8 liters
Bore 4.40 in 4.40 in
Stroke 4.40 in 5.20 in
Valvetrain 2 valves per cylinder
Injection Bosch mechanical injection pump
Aspiration: Turbocharged, Garrett T04E turbocharger (naturally aspirated versions produced for certain agricultural applications)
Horsepower* 160 hp @ 2,600 rpm
165 hp @ 2,600 rpm
170 hp @ 2,600 rpm
185 hp @ 2,400 rpm
210 hp @ 2,400 rpm
215 hp @ 2,400 rpm
225 hp @ 2,400 rpm
240 hp @ 2,400 rpm
Torque* 378 lb-ft @ 1,600 rpm
388 lb-ft @ 1,600 rpm
402 lb-ft @ 1,600 rpm
457 lb-ft @ 1,600 rpm
509 lb-ft @ 1,600 rpm
593 lb-ft @ 1,600 rpm
606 lb-ft @ 1,600 rpm

*Common horsepower/torque ratings published in brochures for various Ford products; additional ratings may have been available and will vary by application.