MT75 Gearbox
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, clutch's / 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)
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.There are several bellhousings, input shaft lengths, gear lever positions, flywheel are different etc.
As you can see there are a number of bellhousings:
Sierra 2.0 DOHC MT75 Gearbox Bellhousing
Transit 2.5 Di Diesel MT75 Gearbox Bellhousing
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 clutch lever suggests it is Left hand drive.
I know they produced a couple V6 ambulances, so maybe it’s something similar?
1996 to 1998 Gears
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
- Drive shaft
- Front gear housing (clutch housing)
- Rear gear housing
- Selector shaft
- Shift Rod – external
- Gear lever
- Crossbar switch
- Drive flange
- Main shaft with gear wheels, bearings and synchroniser
- Counter-shaft gear assembly
- The front gear case and clutch housing.
- The gearbox housing is made of Aluminium and consists of two halves.
- 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.
Ford MT 75 5-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 aluminum Gear 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.
- Roller bearings – countershaft
- Ball Bearings – Drive Shaft
- Bore – selector shaft
- Radial ball bearings – shift shaft
- Ventilation hole
- 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
- Rear gear housing
- Ball bearings – main shaft
- Plate – ball bearings / main shaft
- Fastening screws for mounting plate (3 pieces)
- Locking – circuit (rotation)
- Radial ball bearings – shift shaft
- Radial Seal – selector shaft
- Radial sealing ring – main shaft
- 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.
The figure shows important attachments and
fixtures
MT75 Gearbox Attachments
Gear- Lock – selector shaft
- Switch – Reversing lamps
- Locking screw – lock plate with gear ventilation
- Housing bolts (10)
- Fixing shift gate
- Crossbar switch
- Mounting – Shifters
- Mounting hole (connection for taximeter, if fitted)
- Fixing switching Traverse
- Oil drain plug
- Fixing reverse – idler
- Guide pin
- Oil filler plug
Ventilation
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.
- Front gear housing.
- Locking screw with Ventilation hole.
- Rear gear housing.
1. Shift knob – wiring
- Sleeve – reverse lock
- Gear lever
- 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
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 selected in the usual manner.
- Gaitor
- Spring
- Draw – reverse lock
- 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. Sleeve – reverse lock
To remove the transmission, the gear shift lever is removed.
- Gear lever
- Rod (outside)
- Gaitor
- Cross member
- Gaitor
- Selector shaft oil seal
- Selector shaft (s)
- Rear gear housing
- Rubber block
- Main selector shaft
- Shift fork 3 / 4 Gear
- Radial ball bearings (8 pieces)
- In addition to selector shaft
- Shift fork 1 / 2 Gear
- Shift fork 5 and reverse
- Contact pin holder
- Spring support
- Radial seal
- Circlip
- Spring plate
- Spring
- Reverse lock
- Shift gate
- Locking plate
- Switching finger
- Switch – Reversing lamps
- Actuating pin – reverse light switch
- 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.
- Shift gate
- Reverse lock
Transmission Construction
- Circlip
- Ball Bearings – Drive Shaft
- Circlip
- Drive shaft
- Synchronous Ring 4 Gear
- Needle bearing – drive shaft
- Circlip
- Synchronizer 3 / 4 Gear
- Synchronous Ring 3 Gear
- 3rd gear Gear
- Needle bearing 3 Gear
- Inner race ring 3 Gear
- Needle bearing 2 Gear 14th Gear 2 Gear
- Synchronous Ring 2 Gear
- Circlip
- Synchronizer 1 / 2 Gear
- Synchronous Ring 1 Gear
- 1st Gear Gear
- Needle bearing 1 Gear
- Main shaft
- Needle roller bearings
- Reverse gear
- Synchronizer ring reverse
- Synchronizer 5 and reverse
- Backup ring 27 Synchronous ring 5 Gear
- 5th Gear Gear
- 5th needle bearing Gear
- Ball bearings – main shaft
- Spacer
- Speedo drive
- Output flange
- Nut
- Stock – countershaft
- Inner race – countershaft
- Gearing – Gear Block
- Reverse-idler
- Drive shaft
- Drive gear wheel
- Synchronous fourth cone Gear
- Synchronizer ring
- Guide bearing – Main shaft
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
- Guide sleeve
- Radial seal
- Thrust washer
- Thread (1.5 mm pitch)
- O-ring
- Polygon
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).
- Housing
- O-ring
- Thread (pitch 1.5 mm)
- Allen (17.0 mm)
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.
- Needle bearing – drive shaft
- Circlip
- Synchronizer 3 / 4 Gear
- Synchronous Ring 3 Gear
- 3rd gear Gear
- Needle bearing 3rd Gear
- Internal bearing race – needle bearing 3 Gear
- Needle bearing 2nd Gear
- Gear 2 Gear
- Synchronous Ring 2nd Gear
- Circlip
- Synchronizer 1 / 2 Gear 13th Synchronous Ring 1 Gear
- 1st Gear Gear
- Needle bearing 1st Gear
- Main shaft
- Needle bearing reverse
- Reverse gear
- Synchronizer ring reverse
- Synchronizer 5th and reverse
- Circlip
- Synchronous ring 5th Gear
- 5th Gear Gear
- 5th needle bearing Gear
- Rear gear housing
- Plate
- Ball bearing – main shaft
- Roller bearings – countershaft
- Mounting screws – plate (3 pieces)
- Main shaft
- Internal bearing race – needle bearing 3 Gear selection wheel.
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.
- Rear gear housing
- Radial seal
- Output flange
- Nut (self locking)
- Speedo drive
- Space
Gear Wheels
The Gear wheels of the MT 75 transmission are made of two parts:
The gear body- 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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