5.7 L Olds Diesel
Oldsmobile designed and built the 5.7 L Olds diesel in response to the oil crisis of the late 70's. First appearing in 1978, the 350 ci diesel promised the creature comforts of a large vehicle with the fuel mileage of a compact. Officially named the LF9 diesel, the Olds diesel found its way into Chevrolet, Buick, Pontiac, Oldsmobile, & Cadillac car lineups, as well as light duty Chevrolet & GMC trucks. The engine proved unreliable & problematic. Coupled with a generation of consumers who were unfamiliar with diesel engines, the engine was removed from production despite majority of the flaws being removed. The 5.7 L Olds diesel is responsible for giving diesel engines a poor reputation & setting a grim image for the future of diesel technology. Aftermarket solutions have since proven that the 5.7 L can be transformed into a very capable, fuel efficient solution.
5.7 L Olds Specifications:
| Manufacturer: | Oldsmobile |
| Production Years: | 1978-1985 |
| Applications: | Chevrolet, Buick, Pontiac, Oldsmobile, & Cadillac cars. GMC & Chevy light duty trucks. |
| Configuration: | V-8 |
| Displacement: | 350 cubic inches, 5.7 Liters |
| Compression: | 22.5:1 |
| Bore: | 4.057 inches |
| Stroke: | 3.385 inches |
| Injection: | indirect injection (IDI) |
| Aspiration: | naturally aspirated, non-turbo |
| Peak Horsepower: | 125 HP @ 3,600 RPM |
| Peak Torque: | 225 lb-ft. @ 1,800 RPM |
| Reputation: | Unreliable, poorly designed, problematic. |
Additional 5.7 L Information:
- Though the Olds diesel shares many design similarities with the 350 ci gasoline engine, they are completely different engines. They do not use the same block, and the internals are completely different. Because they share the same bore & stroke as the 350 gasser, people commonly assume the 2 engines share a uniform design.
- The 350 diesel Olds made Popular Hot Rodding's "Worst Automobile Engines of All Time".
- The 5.7 diesel was designed to increase fuel mileage in GM's product line.
- Some drag racers have been known to use 350 diesel blocks as their platform for a 350 ci gasoline engine build, because the blocks are much stronger in high horsepower applications.
Common 5.7 L Olds Diesel Problems:
- Torque to yield (TTY) head bolts provide poor mounting of the cylinder heads. As a result, head gaskets could wear & fail. Head bolts were even know to sheer under the extreme cylinder pressures (the Olds diesel had a very high compression ratio, which didn't help).
- The fuel system lacks a fuel-water seperator. Any water that enters the injection pump can cause parts to corrode & fail. This can result in extensive engine damage.
- Main bolts were too short, often resulting in bottom end failure & crankshaft damage.