Toyota W transmission

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Toyota Motor Corporation's W family is a family of RWD/4WD transmissions built by Aisin. Physically, these transmissions have much in common (like the bell housing-to-body bolt pattern) with other Aisin-built transmissions, like the Jeep AX-5 and the Toyota G-series. The W55, W56, W57, W58, and W59 are externally and internally very similar aside from the gear ratios.

Contents

[edit] W40

4-speed transmission offered in base model vehicles.

Ratios:

  • First Gear: 3.287:1
  • Second Gear: 2.043:1
  • Third Gear: 1.394:1
  • Fourth Gear: 1.00:1
  • Reverse: -4.091:1

Applications:

[edit] W45

Little information is available for the W45 but service documentation from around 1980 lists it as being the 4-speed variant of the W55. It was used in Toyota RWD cars from around the same year.

The W45 was comprised of all aluminum alloy.

Ratios:

  • First Gear: 3.566:1
  • Second Gear: 2.056:1
  • Third Gear: 1.384:1
  • Fourth Gear: 1.00:1
  • Reverse: -4.091:1

Applications: ~1980 RWD Toyota Cars

[edit] W50

Often called the "steel-case" transmission for its steel shell, in contrast to the later W-series transmissions' aluminum case.

Ratios:

  • First Gear: 3.287:1
  • Second Gear: 2.043:1
  • Third Gear: 1.394:1
  • Fourth Gear: 1.00:1
  • Fifth Gear: 0.853:1
  • Reverse: -4.039:1

[edit] W51

Very little information is available about this transmission but it appears to be a model used between the W50 and the W55.

Composition is steel.

Ratios: Unknown

Applications: Later models of Toyota RWD cars with R and T engines.

[edit] W52

Very little information is available about this transmission but it appears to be a model used between the W51 and the W55.

Composition is steel.

Ratios: Unknown

Applications: Unknown

[edit] W55

This was the first of the aluminum-shelled W-series transmissions.

The W55 appears to be a base reference point for gear ratios that Toyota used to fine tune later models of the W-series.


Ratios:

  • First Gear: 3.566:1
  • Second Gear: 2.056:1
  • Third Gear: 1.384:1
  • Fourth Gear: 1.00:1
  • Fifth Gear: 0.85:1
  • Reverse: -4.091:1

Applications:

[edit] W56

A common truck transmission that came in 2-wheel and 4-wheel drive varieties.

Its ratios differ in comparison to the base W55 in the 1st and 2nd gears only; this is to allow a slightly heavier vehicle (truck) to get up to speed slightly quicker than if geared like a car.

This was most likely accomplished by taking the W55 base gears and changing the 1st and 2nd gear sets, as the rest of the transmission remains unchanged.


Ratios:

  • First Gear: 3.954:1
  • Second Gear: 2.141:1
  • Third Gear: 1.384:1
  • Fourth Gear: 1.00:1
  • Fifth Gear: 0.85:1

Applications:

[edit] W57

It differs from the W58 only in its fifth-gear ratio.

The W57 is sometimes designated as a "Close-ratio transmission", however in its stock form it does not meet all the criteria for a Close-ratio box.

The ratio shift was accomplished by taking the W55 base ratios and changing the input shaft to intermediate shaft ratio by 7.9%, thus shifting 1,2,3 ratios higher by that amount (4th is direct 1:1).

Unlike in the W58 the 5th/overdrive gear set was changed to create a smaller rpm drop between 4th & 5th gears so as to remain close to the overdrive ratio seen in the other boxes.

The rest of the transmission remains unchanged.


Ratios:

  • First Gear: 3.285:1
  • Second Gear: 1.894:1
  • Third Gear: 1.275:1
  • Fourth Gear: 1.00:1
  • Fifth Gear: 0.861:1
  • Reverse: -3.768:1

Applications:

[edit] W58

This transmission is very popular as a replacement of other vehicles' weak stock transmissions. It came in two varieties: the original found in the 1982-1989 non-turbo Supras, Celicas and Cressidas of the early 1980's; and the version found in Mk3, Mk 4 Supras and Lexus SC 300s. The latter version has some differences from the earlier version.

Toyota lists a change from an alloy sandwich plate to a steel sandwich plate around 1989. The steel sandwich plate has some minor internal differences, and it is believed to be slightly stronger (some wider bearings, some wider gears, slightly different gear selection mechanism etc). In theory the all alloy version of the W58 should be the exact same strength as any other all alloy W-Series transmission. The steel plate version is considered much harder to find and worth approximately three to five times as much as an all alloy version.

The ratios and bolt patterns remain the same regardless of the sandwich plate used.

The W58 & W57 share the highest gearing and closest ratios (1st,2nd,3rd distance to 4th/Direct) of any of the stock W-Series transmissions.

The ratio shift was accomplished by taking the W55 base ratios and changing the input shaft to intermediate shaft ratio by 7.9%, thus shifting 1,2,3 ratios higher by that amount (4th is direct 1:1), this also shifted 5th/overdrive gear higher by the same amount creating a wider/taller overdrive ratio.

The W58 is sometimes designated as a "Close-ratio transmission", however in its stock form it does not meet all the criteria for a Close-ratio box.

Toyota engineers have shown favor to the W58 over the rest of the 'W' series by including it in so many models and even building a stronger version for higher powered applications.


Ratios:

  • First Gear: 3.285:1
  • Second Gear: 1.894:1
  • Third Gear: 1.275:1
  • Fourth Gear: 1.00:1
  • Fifth Gear: 0.783:1
  • Reverse: -3.768:1

Applications:

[edit] W59

A common truck transmission, this was the successor to the W56. Like the W56, it came in both 2-wheel and 4-wheel drive versions.

This model appears to have a combination of ratios used in older models of the W-series.

  • 1st and 2nd are low ratios like in the W56 for use to get a heavy vehicle moving.
  • 3rd ratio is the same as in the W57/W58 for a lower rpm drop between 3rd & 4th useful in high-speed acceleration.
  • 4th is direct 1:1 as per design in these boxes.
  • 5th seems to be the base W55 overdrive ratio.


Ratios:

  • First Gear: 3.954:1
  • Second Gear: 2.141:1
  • Third Gear: 1.275:1
  • Fourth Gear: 1.00:1
  • Fifth Gear: 0.85:1

Applications:

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