Land Rover Series 2, 2a, 3 Overdrive. I think This unit is the original Santana GLR120A unit (or the later HST SuperDrive) which was designed in the early 1980s in reaction to overdrive problems that occurred with the use of the more powerful 3,4 ltr. 6 cylinder diesel in the 109 Series IV at that time.
Santana made many improvements to increase the strength, reliability and durability. This re-designed unit was very successful for many years. I havent used the overdrive, so I dont have any first hand knowledge of its condition. However I was assured by the previous owner that it was in full working order.
And fits all series gearboxes. The item "Land Rover Series 2, 2a, 3. HST SuperDrive Santana GLR120A Overdrive" is in sale since Monday, April 13, 2020. This item is in the category "Vehicle Parts & Accessories\Car Parts\Transmission & Drivetrain\Gearboxes & Gearbox Parts".The seller is "fangwoo2" and is located in Tring. This item can be shipped to United Kingdom.