MT75 Gearbox

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The MT75, 5 speed gearbox was designed by Ford to replace the T5. It is a rear wheel drive (rwd) 5 speed gearbox that has synchromesh on all gears including reverse, meaning reverse can be selected whilst the car is travelling forward up to 25mph. The MT75 comes in many guises. There are a bewildering array of bellhousing configurations, main shaft lengths, clutchs / flywheels, gear ratio sets, gear-level positions, propshaft fitments and even two different 4×4 versions. Although only rated by Ford at 220Nm (torque) many have been used in Kit Cars and Hot Rods with substantially more.

The gearbox casing is all aluminium and due to the integral bellhousing, swapping gearboxes between different models with different engines can be a very complex and involved job best left to the professionals. Certainly not a 30 minute, quick ‘in and out’ job. Even the 2.0 pinto and the 2.0 Cosworth (essentially the same block) have different bellhousing patterns. Often, getting a gearbox to bolt up and work may require several donor gearboxes to be dismantled for parts. Most swaps can be done, but as parts are getting more rare and expensive, ‘patience’ might also be on your shopping list.

The MT75 gearbox was fitted to several cars and vans:

  • Ford Sierra Cosworth 2wd (Pinto derived Cosworth 16v)
  • Ford Sierra (2.0 DOHC)
  • Ford Sierra xr4i (Cologne v6)
  • Ford Granada (2.0 DOHC)
  • Ford Granada (Cologne v6)
  • Ford Scorpio (Cologne v6)
  • Ford Ultima (Cologne v6)
  • Ford Transit van
  • Ford Transit van 350 (Duratorq 2.4 v6)
  • LDV 350 van (Duratorq 2.4 v6)
MT75 Gear Ratios
Engine 1st 2nd  3rd 4th 5th  Rev
2.0 litre DOHC 8v 3.89 2.08 1.34 1.0 0.82 3.51
2.0 litre DOHC 16v 3.61 2.08 1.44 1.0 0.83 3.26
2.3 litre DOHC 16vMay ’97 3.61 2.08 1.44 1.0 0.83 3.26
2.3 Litre DOHC 16May ’98 3.61 2.08 1.36 1.0 0.76 3.26
2.5 TCi Diesel 3.61 2.08 1.36 1.0 0.76 3.26

There are several bellhousings, input shaft lengths, gear lever positions, flywheel are different etc.

The Ford Sierra 2.0 DOHC bolt pattern is shown in the drawing below. It is very similar to the 2.0 Cosworth MT75 but has less bolts and the starter motor is in a different position.

As you can see there are a number of bellhousings:

Sierra Cosworth 2.0 litre MT75 Gearbox Bellhousing

Sierra Cosworth 2 litre MT75 Bellhosuing

Sierra Cosworth Bellhousing Bolt Pattern

Sierra 2.0 DOHC MT75 Gearbox Bellhousing

Sierra 2.0 DOHC MT75 Gearbox Bellhousing

Although the top bolt pattern is similar to the 2litre Cosworth Bellhousing the bottom bolt pattern is different.

MT75 Gearbox Bolt Pattern - Sierra 2.0 DOHC

MT75 Gearbox bolt pattern and dimensionsDownload the 2.0 DOHC MT75 Gearbox bolt pattern and dimensions

 

Sierra V6 MT75 Gearbox Bellhousing

Sierra v6 MT75 gearbox Bellhousing

MT75 Gearbox Dimensions

Transit / LDV 350 2.4 litre Duratorq MT75 Gearbox

Transit 350 Duratorq MT75 Gearbox Bellhousing

The Transit LT350 2.4 diesel Gearbox is available with 3 and 4 bolt propshaft flanges.

Transit 350 Duratorq Gearbox

LDV MT75 GearboxDownload the LDV Single Rail Gearbox Service Manual here

 

Transit 2.5Di Diesel MT75 Gearbox Bellhousing

Transit 2.5Di MT75 Gearbox Bellhousing

Transit MT75 gearbox

Others

I’m not sure what this one is but it is an MT75.

From the Bellhousing it looks like a V6 and from the gear level position it looks like a Transit. The cluch lever sugests it is Left hand drive.

I know they produced a couple V6 ambulances, so maybe it’s something similar?

MT75 exploded diagram

MT75 exploded diagram

MT75 exploded diagram

MT75 exploded diagram

MT75 Selector

Then there is also the:

  • 2.0 DOHC Transit (similar bolt pattern to the DOHC Sierra but with a different gear lever arrangement).

There are also different length main shafts, different clutch and flywheels etc.

MT75 Repair Manual

MT75 Cross Section

  1. Drive shaft
  2. Front gear housing (clutch housing)
  3. Rear gear housing
  4. Selector shaft
  5. Shift Rod – external
  6. Gear lever
  7. Crossbar switch
  8. Drive flange
  9. Main shaft with gear wheels, bearings and synchroniser
  10. Counter-shaft gear assembly

The gearbox housing is made of aluminium and consists of two halves

  • the front gear case and clutch housing
  • the rear gear case

The usual gear extension does not apply to this transmission. This had a weight saving of approximately 7.0 kg and reduced the entire length.

The transmission was improved by the following measures:

  • Increased synchronisation
  • Shorter shifting travel
  • New gear lever guide
  • Needle-mounted gear wheels
  • Two ball sleeve-mounted shift shaft
  • High quality gear oils

Gear ratios were tuned to provide good performance and economy. By changing from 4th to 5th engine speed can reduce engine speed by 1000rpm. When this gearbox came out 4 speed was norm, 5 gears reduce engine emissions, noise and wear.

  • All gears are hardened to substaintially improve the smoothness of the transmission.
  • The reverse gear is synchronised.
  • All gear wheels are mounted on needle bearings.

All of these help to optimise the ride quality and driving comfort.

Comparison of MT75 and Type 9 Gearboxes

Ford MT 755-speed manual transmission

Previous 5-speed manual transmission (Type 9)
Maximum Torque
300 Nm – 221 ft/lbs
220 Nm -162 ft/lbs
Weight
35,0 kg
42,0 kg
Transmission length
638 mm
772 mm
Gear wheels (all) Needle bearing no needle bearings
Gears 2-piece welded one-piece
Reverse gear synchronized not synchronized
Clutch and gearbox Two-piece die-cast aluminumGear extension is not necessary. Three-piece cast iron.Gearbox extension of die-cast aluminum
Oil Capacity 1.2 Liter 1.9 Liter

The MT 75 transmission consists of two halves, the front transmission housing or clutch housing and the rear gear housing.

Front gear housing

MT75 Front Casing

  1. Front gear housing or clutch housing
  2. Roller bearings – countershaft
  3. Ball Bearings – Drive Shaft
  4. Bore – selector shaft
  5. Radial ball bearings – shift shaft
  6. Ventilation hole
  7. Circlip

The front gear box features three bearings

  • The ball bearing for guiding the drive shaft
  • the roller bearings for the countershaft
  • the ball sleeve bearing for the selector shaft

The drive shaft ball bearings are sealed with an oil seal in the guide sleeve. The thread of the guide sleeve within gear housing is sealed with an O-ring seal.

The roller bearing and the bearing bracket from the transmission are also sealed with an O-ring seal. The selector shaft has a ball sleeve bearing in the front gearbox.

The bore-selector shaft has a ventilation hole for the shift shaft.

All bearings in the front housing are replaceable.

To adapt to the different engine options and for left-and right-hand drive vehicles, different front gear housings are available.

Note:

  • The drive shaft ball bearings must point to the inside cover of the transmission housing.
  • The countershaft roller bearing are paired (inner and outer ring) and thus must be from one manufacturer.

Rear Gear Housing

MT75 Rear Gear Hosuing

  1. Rear gear housing
  2. Ball bearings – main shaft
  3. Plate – ball bearings / main shaft
  4. Fastening screws for mounting plate (3 pieces)
  5. Locking – circuit (rotation)
  6. Radial ball bearings – shift shaft
  7. Radial Seal – selector shaft
  8. Radial sealing ring – main shaft
  9. Roller bearings – countershaft

There are three bearings in the rear housing:

  • main shaft ball bearing
  • countershaft roller bearings
  • ball sleeve bearing for the selector shaft

The countershaft ball bearings are pressed into the rear gearbox.

The ball sleeve bearing and the selector shaft is sealed by a radial seal at the rear gearbox.

The main shaft is sealed with a radial sealing ring.

The locking pin in the rear transmission housing is used to prevent rotation of the selector mechanism.

All bearings and radial seals are replaceable.

Note:

The main shaft ball bearing must point to the inside cover of the transmission housing.

The roller bearings (inner and outer bearing) for the reduction gearing must be from one manufacturer.

Gearbox Attachments

The two halves of the transmission casing are held together by 10 bolts. Two guide pins center the two gearbox halves. The switch for the reversing lights is attached to the front gearbox housing. The switch is actuated by a selector shaft pin.

MT75 Gearbox Attachments

The figure shows important attachments and fixtures

  1. Gearbox
  2. Lock – selector shaft
  3. Switch – Reversing lamps
  4. Locking screw – lock plate with gear ventilation
  5. Housing bolts (10)
  6. Fixing shift gate
  7. Crossbar switch
  8. Mounting – Shifters
  9. Mounting hole (connection for taximeter, if fitted)
  10. Fixing switching Traverse
  11. Oil drain plug
  12. Fixing reverse – idler
  13. Guide pin
  14. Oil filler plug

Ventilation

There is a ventilation air hole in the locking screw for the locking plate.

When repairing, ensure that the vent is free of dirt and debris. A clogged transmission vent can create unwanted pressure. A blocked vent will result in Oil leaks, spills and lack lubricant.

MT75 Ventilation

  1. Front gear housing
  2. Locking screw with Ventilation hole
  3. Rear gear housing

Gear Shift

MT75 Gear Shift

  1. Shift knob – wiring
  2. Sleeve – reverse lock
  3. Gear lever
  4. Draw – reverse lock

The shifter is a complete unit and in the case of failure must be completely replaced.

The shifter is not the usually fixed to the gear extension, but onto the control beam, which is attached to the gear housing.

MT75 Gear Lever

Gears are selected using the shift lever, the outer plate and inner shift shaft. The reverse gear is synchronized. The reverse gear can be selected only in the neutral position and by pulling up the reverse lock on the gear lever. The forward gears are seected in the usual manner.

  1. Gear lever
  2. Sleeve – reverse lock
  3. Gaitor
  4. Spring
  5. Draw – reverse lock
  6. Shift Rod – external

External selection assembly

The outer transmission circuit consists essentially of the gear lever, the arm and the switching beam. A setting of the shift rod is not provided. The switching beam is fixed at four points on the rear gear housing. To remove the transmission, the gear shift lever is removed.

MT75 Lever Assembly

  1. Gear lever
  2. Rod (outside)
  3. Gaitor
  4. Cross member
  5. Gaitor
  6. Selector shaft oil seal
  7. Selector shaft (s)
  8. Rear gear housing
  9. Rubber block

 Internal Selection Assembly

MT75 Internal selection assembly

  1. Main selector shaft
  2. Shift fork 3 / 4 Gear
  3. Radial ball bearings (8 pieces)
  4. In addition to selector shaft
  5. Shift fork 1 / 2 Gear
  6. Shift fork 5 and reverse
  7. Contact pin holder
  8. Spring support
  9. Radial seal
  10. Circlip
  11. Spring plate
  12. Spring
  13. Reverse lock
  14. Shift gate
  15. Locking plate
  16. Switching finger
  17. Switch – Reversing lamps
  18. Actuating pin – reverse light switch
  19. Shift shaft lock

The internal selection assembly consists essentially of the shift shaft, the shift forks, shift interlock and the shift gate. The main selector shaft is mounted within a ball bearing sleeve. The main selector shaft is moved from the outer plate axially and radially.

The main selector shaft contains the following components:

  • shift finger, which is pinned to the main selector shaft
  • Lock plate
  • Switching pen holder, also pinned to the main selector shaft
  • Locking device for the gears 1-3-5, Neutral, and 2-4-reverse
  • actuating pin to the reverse light switch
  • Shift fork for 1st and 2 Gear
  • Spring to keep the selector shaft in neutral position

On the side selector shaft is:

  • the shift fork for the 5th and reverse gear
  • the shift fork for 3rd and 4th Gear

A light press fit helps guide the secondary selector shaft in the front and rear gear case.

The shift forks are mounted on the shifting shafts with radial ball bearings.

Note:

The ball sleeve bearings of the main and secondary shafts and the shaft of the shift forks (total 8 pieces) are identical.

Before installation, the ball sleeve bearings are wetted with specified gear oil.

The shift gate is secured with two fitting bolts on the rear gearbox.

The reverse lock is attached the shift gate and secured with a clip .

MT75 Gate

  1. Shift gate
  2. Reverse lock

 Transmission Construction

MT75 Construction

  1. Circlip
  2. Ball Bearings – Drive Shaft
  3. Circlip
  4. Drive shaft
  5. Synchronous Ring 4 Gear
  6. Needle bearing – drive shaft
  7. Circlip
  8. Synchronizer 3 / 4 Gear
  9. Synchronous Ring 3 Gear
  10. 3rd gear Gear
  11. Needle bearing 3 Gear
  12. Inner race ring 3 Gear
  13. Needle bearing 2 Gear 14th Gear 2 Gear
  14. Synchronous Ring 2 Gear
  15. Circlip
  16. Synchronizer 1 / 2 Gear
  17. Synchronous Ring 1 Gear
  18. 1st Gear Gear
  19. Needle bearing 1 Gear
  20. Main shaft
  21. Needle roller bearings
  22. Reverse gear
  23. Synchronizer ring reverse
  24. Synchronizer 5 and reverse
  25. Backup ring 27 Synchronous ring 5 Gear
  26. 5th Gear Gear
  27. 5th needle bearing Gear
  28. Ball bearings – main shaft
  29. Spacer
  30. Speedo drive
  31. Output flange
  32. Nut
  33. Stock – countershaft
  34. Inner race – countershaft
  35. Gearing – Gear Block
  36. Reverse-idler

Drive Shaft

MT75 Drive shaft

  1. Drive shaft
  2. Drive gear wheel
  3. Synchronous fourth cone Gear
  4. Synchronizer ring
  5. Guide bearing – Main shaft

On the drive shaft is the drive wheel of the layshaft and the synchronizer for the 4th Gear. The drive shaft is mounted in the front gear case in a ball bearing. The ball bearing is held axially by a retaining ring in the transmission housing.

Note:

There are different drive shafts for the different gear ratios and engine versions. The drive shafts therefore differ not only by the number of teeth, but also in length. Therefore, it is important that the part number, engine and vehicle model information is used to obtain a replacement.

Guide Sleeve – Driveshaft

MT75 Guide Sleeve

  1. Guide sleeve
  2. Radial seal
  3. Thrust washer
  4. Thread (1.5 mm pitch)
  5. O-ring
  6. Polygon

The guide sleeve is made of aluminum and is screwed into the front gearbox. There is a thrust washer in the guide sleeve, for the front bearings of the main shaft. The guide sleeve has a radial seal and an O-ring, they can be replaced in service. Before fitting, clean the threads of the guide sleeve and the threads of the front transmission case. Prior to driving, the radial seal and the O-ring replaced and are wetted with specified gear oil. The guide sleeve is screwed in with a special tool 16-040 in the front gear housing and tightened to 150 – 170Nm.

Countershaft gear assembly housing

The bearing for the countershaft is held in position by the bearing housing and sealed with an O-ring seal. The O-ring seal can be replaced in service. The housing is made of aluminum and is screwed into the front gear case and secured with a locking plate. The housing can be installed with a commercially available internal hex wrench (17.0 mm).

MT75 Housing

  1. Housing
  2. O-ring
  3. Thread (pitch 1.5 mm)
  4. Allen (17.0 mm)

Before installation, clean the thread of stockholders and the thread in front gearbox housing. Then wet the O-ring seal to be replaced with specified gear oil.

MT75 Housing

After installation, the bearing holder is tightened to 20 ± 5 Nm and then rotated by 60°. Then with two blows of a brass spike and hammer hit the slugs, so that there is bearing clearance. It must be possible to turn the input shaft by hand. This ensures that the bearing is seated. Thereafter, the bearing housing is secured with the locking plate (see workshop manual). 1. Bearing Housing – Allen (17.0 mm) 2. Locking plate (screw with 9.0 to 11.0 Nm) 3. Guide sleeve – drive shaft 4. Slugs

Main Shaft

MT75 Main Shaft

  1. Needle bearing – drive shaft
  2. Circlip
  3. Synchronizer 3 / 4 Gear
  4. Synchronous Ring 3 Gear
  5. 3rd gear Gear
  6. Needle bearing 3rd Gear
  7. Internal bearing race – needle bearing 3 Gear
  8. Needle bearing 2nd Gear
  9. Gear 2 Gear
  10. Synchronous Ring 2nd Gear
  11. Circlip
  12. Synchronizer 1 / 2 Gear 13th Synchronous Ring 1 Gear
  13. 1st Gear Gear
  14. Needle bearing 1st Gear
  15. Main shaft
  16. Needle bearing reverse
  17. Reverse gear
  18. Synchronizer ring reverse
  19. Synchronizer 5th and reverse
  20. Circlip
  21. Synchronous ring 5th Gear
  22. 5th Gear Gear
  23. 5th needle bearing Gear

The main shaft is mounted in the rear transmission housing in a ball bearing. The drive shaft in front of the main shaft is guided by roller bearings. The ball bearings are held in place by a retaining plate in the rear gear housing. The mounting plate is secured with 3 screws in the rear gearbox.

MT75 Main Shaft Bearing

  1. Rear gear housing
  2. Plate
  3. Ball bearing – main shaft
  4. Roller bearings – countershaft
  5. Mounting screws – plate (3 pieces)

All Gear wheels are mounted on needle bearing. Thus the shiftability transmission is significantly improved. The needle bearing of 3. Gear Selection wheel running on an internal bearing race. The inner bearing race and the needle bearing are paired, so must be replaced together.

MT75 Gear Selection

  1. Main shaft
  2. Internal bearing race – needle bearing 3 Gear selection wheel

To renew the Internal bearing race of 3rd Gear wheel is heated with a heat gun (100 ° C), released with two suitable levers from it’s seat and taken off of the main shaft with a standard 2-arm puller. The Internal ring must not be overheated when heated.

The gears and synchronizer are held in place by three retaining rings. The retaining rings are available in different strengths in order to ensure the required mounting tolerances.

The main shaft is sealed in the rear gear housing with a radial sealing ring. This seal can be replaced with the transmission installed.

MT75 output flange

  1. Rear gear housing
  2. Radial seal
  3. Output flange
  4. Nut (self locking)
  5. Speedo drive
  6. Space

Gear Wheels

The Gear wheels of the MT 75 transmission are made of two parts:

  1. the gear body
  2. the cone clutch gear

The more recent Gear wheels were manufactured in one piece. For technical reasons, therefore had an approximately 4.0 mm wide machined nut placed between the running and the clutch teeth.

To optimize the smoothness compared to the previous design, the 2-piece gear design made it possible to tune the running gear after hardening and correct any hardening distortions.

After processing of the gear body and the cone clutch teeth, both parts are joined together so that as the later weld hardens no carbon forms.

After the curing process, the cone is separated from the tooth body to (grind) treat the running gear.

The advantages of this new technology are:

  • Optimum gear quality by treatment of the teeth (grinding)
  • Improved smoothness
  • More compact gear unit
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