Borg-Warner 35 transmission

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The Borg-Warner 35 (or BW-35) is an automatic transmission produced by the BorgWarner company. It has three forward and one reverse gears. The selector lever follows a quadrant which has six stations (Park, Reverse, Neutral, Drive, Second gear and First gear). The "3" in the model number refers to the number of forward gears.

Contents

[edit] Description

When the transmission of the motionless vehicle is placed in Drive, the transmission allows the vehicle to move off in first gear, then will change to second and then to third gear based on increase in road speed. The BW-35 will downshift from third to second and from second to first, also based on load. The transmission is equipped to produce kickdown and will upshift after kickdown if accelerator pressure is released following a kickdown.

As is common in automatic transmissions of its generation, power brought to the transmission via the torque converter drives hydraulic fluid. As the gears move faster or slower, pressure of the fluid increases or decreases in the case. Mechanical switching of gears is triggered by the increase or decrease of pressure. There are no electronic sensors or switches as found in modern transmissions .


The Borg Warner 35 automatic transmission comprises a torque converter and a fully automatic 3 speed hydraulically controlled epicyclic gear box. The automatic transmission provides 3 forwards and one reverse gear ratio.

The hydraulic control system consists of a valve arrangement and an engine driven pump. The automatic transmission contains a planetary gear set consisting of 2 sun gears, 2 sets of three planet pinions contained within a planetary carrier and ring gear. Various speed ratios are obtained by holding or clutching various combinations of elements of the planetary train. This is performed by 2 bands, 2 multi disc clutches and a one way clutch.

[edit] Users

Initially produced in the United States in the 1950s for the Studebaker and American Motors brands, production was transferred in 1960 to Great-Britain. The BW-35 was offered to European automobile producers where it was widely used.

[edit] Datsun

  • 1967 Datsun RL411 SSS (SuperSportSedan) and 1600 ('Bluebird'); (same engine as the SR311 'Fairlady' roadsters).

[edit] MG

  • MGB Mk II
  • MGB GT

[edit] Jaguar

[edit] The Rootes group (United Kingdom)

  • Hillman
  • Humber
  • Singer
  • Sunbeam Alpine

[edit] Daimler-Benz (Germany)

[edit] Volvo (Sweden)

Between 1969 and 1975, BW-35 transmissions were used in 140 and 160 series Volvos. Also 1800 series (E & ES).

Volvo 164 gear ratios were as follows:

  • 1st gear: 2.39:1
  • 2nd gear: 1.45:1
  • 3rd gear: 1:1
  • Reverse: 2.09:1

[edit] Ford (Australia)

  • Escort
  • Cortina (c3 also?)
  • Early ford Falcons (fordomatic)

Escort and Cortina gear ratios were as follows:

  • 1st gear: 2.393:1
  • 2nd gear: 1.450:1
  • 3rd gear: 1.000:1
  • Reverse: 2.094:1

[edit] Chrysler (Australia)

In the early 1970s, The Borg-Warner 35 was also used in 6-cylinder Australian Chryslers, Valiants and Chargers. This was due to the Torqueflite autos being replaced for the need to have more local content.