Oldsmobile produced three versions of a diesel engine between 1978 and 1985: a 350 cu in (5.7 L) V8 in 1978-85, a 261 cu in (4.3 L) V8 in 1979, and a 263 cu in (4.3 L) V6 from 1982 until 1985. The engines powered front and rear-wheel drive vehicles; the 4.3-litre V6 was adapted to both transverse and inline front-wheel drive applications. Sales peaked in 1981 at approximately 310,000 units, which represented 60% of the total U.S. passenger vehicle diesel market. However, this success was short-lived as the V8 diesel engine suffered severe reliability issues. While Oldsmobile had appropriately strengthened the block, they left the head bolt design and pattern unchanged to enable them to use the same tooling as for the gasoline engines. Catastrophic head bolt failures were thus legion, as di