Tech:Engine/K Series/Manual Gearbox

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Corolla manual gearboxes are integral-bellhousing cable-clutch units called the K40 (4 speed) and K50 (5 speed). They are interchangeable over all models, with the only difference being gear ratio over year models, and the shifter position on the extension housing. KE1x have the shifter all the way forward, KE2x 3x and 5x have the shifter in the middle, KE7x have the shifter at the back. Most people tend to prefer the 7x shifting position, even when placed in the earier cars and a hole cut in the floor. Extension housings between 4 and 5 speed are not interchangeable. All K manuals have the same output shaft. If you're building a tough K motor and/or enjoy doing burnouts and giving your driveline a general hard time, K50s are reputed to be weaker than K40s, but some people disagree with this.

According to Toyota parts catalogs, some early 1974 KE35s came out with Celica T50 boxes and a bellhousing to adapt this to the K motor. These bellhousings are quite rare, but not entirely unattainable. A T40 or T50 will bolt into KE2x onwards Corollas, use the rear gearbox crossmember holes in the floorpan. You may have to space up and modify the gearbox crossmember and/or mount where the box joins the crossmember. T gearboxes will fit in factory-auto KE1x cars, manuals will need tunnel mods.

If, somehow, you make a K motor that is so tough it eats T50s on a regular basis, Conversion Components Ltd in New Zealand sell a kit to adapt a K motor to a W55 supra box. These are huge boxes, you're going to have to chop the tunnel in any Corolla you try stuff this box into.

Oil Fill Quantities

K40 - 1.7L K50 - 2.45L T40 & T50 - 1.5L

After you drain the oil, you can either crawl under your car and fill it through the actual filler hole on the side, or (much easier) you can pull the shifter out (undo the 4 bolts, not the circlip) and pour the oil in there slowly.


Oil capacity: 3.0 lmp pints(1.7L)

Synchromesh on all Forward gears


   * First Gear: 3.769:1
   * Second Gear: 2.250:1
   * Third Gear: 1.405:1
   * Fourth Gear: 1.010:1
   * Fourth TRD**: 1.5436:2
   * Reverse Gear: 4.316:1


   * Most 4-speed RWD Tercel, Starlets and Corollas with K-series engines
   * KM20 series LiteAces that were fitted with K-series engines had a standard K40 fitted with a column shifter
   * Toyota Racing Development** has produced a fourth gear closer to third in Ratio


Oil capacity:4.2 lmp pints(2.45L)

Synchromesh on all Forward Gears


   * First Gear: 3.789:1
   * Second Gear: 2.220:1
   * Third Gear: 1.435:1
   * Fourth Gear: 1.000:1
   * Fifth Gear: 0.865:1
   * Reverse gear: 4.316:1


   * Most 5-speed RWD Tercel, Starlets and Corollas with K-series engines.
   * 1986 Corolla with 3A-U and 4A-U engines.
   * KM20 series LiteAces were fitted with K50 transmissions to 4K and 5K engines as an option, and to the 7K as standard.


Doug spotted that there are two different ratios across the series, listed below:

KE10, KE20, KE30, possibly KE55 w/ 4 Spd

1st 3.684 2nd 2.050 with 1K motor, 2.022 with 3K motor 3rd 1.383 4th 1.000 Rev 4.316

KE55 w/ 5 spd, KE70

1st 3.789 2nd 2.220 3rd 1.435 4th 1.000 5th 0.865 Rev 4.316

There were apparently no 5 speeds in KE10s or 20s.

from Helene & Matti's page

<tbody> </tbody>
type reverse 1st 2nd 3rd 4th 5th 6th weight stock hp applications
T40 -3.484 3.587 2.022 1.384 1 - - ~24kg 105 82 Corona (3A), 83 Corona (1S/3T-E), 83 Carina (3A, some), 83 Celica (1S)
T50 -3.484 3.587 2.022 1.384 1 0.861 - 25.5kg 124 124 82-83 Carina (3A/1S/2T-GE/3T-E), 83 Celica (3T-E,2T-GE), 82 Corona (1S), 86 Corolla Levin (4A-GELU, 3A-U/4A-U some)
W55 -4.091 3.566 2.056 1.384 1 0.850 - 35kg 190 82-83 Carina/83+85 Celica/83 Corona (3T-GTE), 86 Soarer/Supra (1G-GE), Crown (1G-E some, 1G-GE, 6M-GE some, 2L/2L-T some), 83+85-86 Cressida/MarkII/Chaser (1S, 21R some, 1G-E some, 1G-GE, 2L/2L-T some)
W5* -4.091 3.566 2.056 1.384 1 0.861 - 35kg 160 85 Carina/Corona (3T-GTE)

T50 Differences

from Helene & Matti's page

From: Scott Davis ([email protected])

There are three versions of the T-50 that I know of. One is pre 1979, and has a different bolt arrangement between the bellhousing and the gearbox. The 80-82 version has a the same bolt arrangement as the 83+ T-50's, but a different (smaller) output shaft diameter."

From: Claudio

"The tailshaft or gear shifter housing on the '80-87 T-50 transmission is longer than the '70-79 models by about 6". The main reason for this change was to bring the shifter further into the passenger compartment. I remember that in my pre '80s Corollas the shift lever came out from the lower part of the dashboard, compared to my later models where it comes out of the floor, just ahead of the seats.

If you run a car in competition, you may want to use the older transmission with the shorter shifter housing. The lever on these models acts directly on the shifter forks. The newer model's shifter must act through an additional linkage, which adds additional vagueness and is less durable, especially when ramming the lever during clutchless shifting. Most later model shifters ('80-87) with high mileage or hard use will be very loose. In almost all cases this looseness will be due to a collapsed nylon bushing on a ball joint at the end of shift lever in the transmission. This bushing cost less than $2US and is easy to replace. Warm the new component in hot water before popping it on the lever to prevent it from breaking.

The early model shifters don't have this problem because it doesn't use the extra linkage and everything is metal to metal, no bushings. If you are replacing this bushing, you might as well remove the other source of vagueness, the rubber bushing in the shift lever rod. It is located about half way down the shifter where the rod bulges. As the years progressed, from 1970 on, this rubber bushing got bigger and bigger in order to increase isolation (vagueness). With the engine off, try to pull the lever down into any gear with increasing pressure and see how much the lever flexes. This movement is due to the rubber bushing. If you truly want to "experience" your machine, remove the rubber bushing. I must warn you, though, that if you grind a gear badly, you will "feel" the mistake all the way up your arm and hurt along with your machine.

The best way to eliminate the rubber bushing is to: - remove the upper part of the lever with the bushing - weld a hollow tube to the bottom part of the lever - weld a stud to the end of the tube for your shift knob - while you're at it, why not make the lever 1" shorter for shorter throws

P.S. I believe that the only difference between the '80-82 (3TC) and '83-87 (4AG,3AC) transmissions were the bellhousing. You should be able to use a short tailshaft '70-79 (direct linkage) T-50 in '84-87 Corollas by using the bellhousing that came with the car. You would also have to cut the shifter hole further forward on the trans. tunnel and likely mix and match driveshafts halves."

C-Series FWD Transmission/Transaxle

The C-series transaxle is the transmission use in all FWD Corollas to date. Below are the variants available and their ratios.

Name 1st 2nd 3rd 4th 5th 6th Notes
C50 3.545 1.904 1.310 0.969 0.815 - AE82, AE92 (All), AE101 w/ 4A-FE
C52 3.166 1.904 1.310 0.969 0.815 - AE102 w/ 7A-FE? AE92 GTi (4A-GE) AE101 Silvertop 20v 1st generation
C56 3.166 1.904 1.392 1.031 0.815 - AE101 Silvertop 20v (2nd generation) & AE111 Blacktop 20v
C59 3.166 1.904 1.310 0.969 0.815 - AE102 w/ 7A-FE?, AE112R (including Sportivo Turbo), Stronger version of C52?
C150 3.545 1.904 1.310 0.969 0.815 - ZZE122R, Stronger version of C50? AE101 4E-FE (1300cc)
C151 3.545 1.904 1.233 0.885 0.725 -
C60 3.166 2.050 1.481 1.166 0.916 0.725 ZZE123R (Sportivo)
C65M 3.166 1.904 1.392 1.031 0.815 0.725 ZZE31 MR2 Spyder, this is the sequential tranmission
C160 3.166 2.050 1.481 1.166 0.916 0.725 AE111 20v Blacktop 6speed
C161 ? ? ? ? ? ? EE111 G6, this was a US spec Corolla with the 4E-FE