The Oliver 1550 and 1555 tractors, produced in the late 1960s to early 1970s, represent a lineage of robust agricultural machinery from the Oliver Farm Equipment Company. These models, part of the White Motor Corporation during their production, are known for their durability and power, embodying the brand's heritage of engineering quality. Designed for agricultural applications, these tractors offer substantial performance, with the 1550 providing approximately 62 PTO HP and the 1555 offering around 70 PTO HP, utilizing diesel engines with displacements of approximately 265 cu in (4.3 L) and 310 cu in (5.1 L) respectively. Their reliable construction and strong operational capabilities made them a valued asset for farm owners and operators. This workshop parts manual provides comprehensive coverage for the Oliver 1550 and 1555 tractors, serving as an essential resource for both owners and repair shops. It details all tractor components with high-quality exploded views, corresponding part numbers, and illustrations, facilitating accurate part identification and ordering. The manual covers critical systems including the engine, transmission, hydraulic system, drivetrain, and electrical components, among others. Its primary purpose is to enable efficient maintenance, repair, and component replacement, ultimately helping to preserve the operational integrity and longevity of these agricultural machines while potentially reducing repair costs through informed part procurement.