Xtracer 1152 User manual

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

1152

Longitudinal Sportscar Transaxle

Gearbox Manual

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

Contents

1. Summary of Lubricants and Greases.................................................................. 4

2. Operating requirements ...................................................................................... 5

3. Specification........................................................................................................ 7

3.1. General Items .............................................................................................. 7

3.2. Standard Options (no cost) .......................................................................... 9

3.3. Optional Extras (cost options)...................................................................... 9

3.4. Excluded Items ............................................................................................ 9

4. Gearbox Operation............................................................................................ 10

4.1. Gearchange Description ............................................................................ 10

4.2. Oil System.................................................................................................. 10

4.2.1. Description............................................................................................ 10

4.2.2. Dedicated Oil Feeds ............................................................................. 11

4.2.3. Sensors ................................................................................................ 11

4.2.4. Filtration and Magnets .......................................................................... 11

4.2.5. Setup/Running Conditions.................................................................... 11

4.3. Gear Cluster............................................................................................... 12

4.3.1. Reverse Gear ....................................................................................... 13

4.4. Differential.................................................................................................. 14

4.4.1. Description............................................................................................ 14

4.4.2. Ramp Angles ........................................................................................ 15

4.4.3. Number of Friction Faces ..................................................................... 15

4.4.4. Positive Preload.................................................................................... 15

4.4.5. Differential Test Rig .............................................................................. 15

5. Gearbox Assembly and Maintenance ............................................................... 16

5.1. General Assembly Notes ........................................................................... 16

5.1.1. Torque Settings .................................................................................... 17

5.2. Cluster Setup ............................................................................................. 18

5.2.1. Ratio Change Procedure ...................................................................... 18

5.2.2. Selector Barrel Setup ........................................................................... 19

5.3. Differential Setup ....................................................................................... 21

5.4. Spiral Bevel Gear Assembly ...................................................................... 21

5.5. Lifing Chart................................................................................................. 21

6. General Information .......................................................................................... 23

6.1. Customer Support...................................................................................... 23

6.1.1. Gearbox & Parts Supply ....................................................................... 23

6.1.2. Training/Servicing................................................................................. 23

6.1.3. Contacts ............................................................................................... 24

7. Appendix A – Non Standard Tightening Torques.............................................. 25

8. Appendix B – Dog Damage Sheet .................................................................... 26

9. Appendix C – Example Bevel Setting Sheet ..................................................... 27

10. Appendix D – Electrical Component Data Sheets .......................................... 28

10.1. Bosch Temperature Sensor NTC M12-L.................................................... 28

11. Appendix E – Oil Pumps and Flow ................................................................. 29

11.1. Oil Pump Pressure and Flow Rates ........................................................... 29

12. Appendix F – Differential Characteristics........................................................ 30

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

13. Appendix G – Example Lifing Sheet............................................................... 32

14. Appendix H – Ratio List-1152B–LMP3 ........................................................... 34

15. Appendix J – Ratio List-1152–Generic ........................................................... 39

16. Appendix K – Manual Revision Sheet ............................................................ 42

17. Appendix L – Exchange Server Log-In Procedure ......................................... 42

18. Appendix M – Xtrac Standards....................................................................... 45

19. Appendix N – Technical Bulletins ................................................................... 50

Issue 1.0 – 21/04/15

Issue 2.0 – 10/12/15

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

1. Summary of Lubricants and Greases

The following lubricants and greases have been used by Xtrac during the assembly

and testing of the 1152 gearbox:

Gearbox Oil Type Xtrac XL1 or any other fully

synthetic SAE 75W90 gear oil.

Assembly Grease Neo Z12 Lithium Grease

O-ring Assembly Grease Polylub Gly 151

Xtrac use various Loctite adhesives for thread locking, bonding and sealing, a list of

which is detailed below:

Loctite 270 All studs fitted into casings

Loctite 648 For high temperature

retention of parts with a clearance

or interference fit i.e. retaining

bushes, bearings, seals.

Loctite 406 Rapid bonding of rubbers when

used with Loctite 7239 Polyolefin

Primer bonds. Used for O-ring

sealing and bonding

Loctite 572 For the locking and sealing of

metal tapered threads and

fittings.

Araldite 2014 For permanent fitment of parts

not to be disassembled i.e.

blanking plugs. Note: all black

casting core plugs are

permanently fitted with Araldite

2014 and no attempt should be

made to remove them.

Lockwire 302 grade Goodridge, 0.81mm

gauge

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

2. Operating requirements

For optimum Performance and Safety – Warranty issues

Xtrac is extremely proud of the quality, success and reputation of their products and

we are delighted that you have chosen to use the 1152 gearbox. The design of each

gearbox is the subject of much research and development, technical analysis and

detailed testing. However, as with all motorsport products, it is vital that they are

correctly maintained and adjusted for each individual circumstance. This manual is

intended to ensure that you obtain the maximum performance and reliability from this

gearbox.

The gearbox should be operated within the temperature and pressure limits given.

Gearbox oil level must be maintained at all times and the oil needs to be replaced

regularly. Gearbox oil and other lubricants used must be as listed in the Xtrac service

documentation.

The life and durability of the gearbox internal parts is considerably influenced by

factors other than engine and chassis characteristics. These can be classified as

gearbox misuse:-

•If the gearbox is damaged in transit, during incorrect installation or as a result

of accident, puncture damage or abnormal weather conditions.

•Inadequate cooling and exceeding operating temperature. Un-approved or

insufficient oil or grease.

•Incorrect maintenance or adjustment or work by unauthorised and/or

untrained personnel.

•Modification or work to any component or use of non Xtrac parts.

•System related sensor, valve and pump failures.

•Engine, gear change or clutch and driveline loads beyond the design limits.

•Exceeding designated life or failure to keep adequate lifing records.

•Engine and/or vehicle dynamometer and rolling road use.

Full and comprehensive lifing records must be maintained by the Customer during

use. We would stress that after each event or prolonged period of running, the

gearbox should be carefully inspected and stripped as appropriate. In the manual

there are lifing recommendations for critical components detailed in section 5.5 -

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

Lifing Chart. If in doubt please contact our Commercial Department who will advise

you or if necessary put you in contact with one of our engineers.

It is important to ensure the correct lubricants are used, such as Xtrac developed

XL1 and XG1, and that all adjustments and tolerances are as specified. The use of

parts not supplied by Xtrac will automatically invalidate any warranty or other liability

which would normally be assumed by Xtrac.

Your attention is drawn in particular to sections 10 and 15 of the Terms and

Conditions of Sales which include the following:

‘…Goods intended for motorsport or for product development, evaluation or

experimentation may operate under extreme loads and conditions and you agree

that it is your responsibility to ensure that the Goods are correctly inspected,

adjusted and maintained at all times to suit the specific conditions in which they may

be used.’

‘Lightweight and weight optimised components are supplied subject to warranty only

against manufacturing defects. It is possible that in certain conditions operating life

may be reduced. Prototype and experimental gearboxes or components

manufactured by us to our design or manufactured by us to your design are supplied

subject to warranty only against manufacturing defects. Subject to Conditions 10.4

and 10.5, any such components or gearboxes, by their very nature, are not

warranted as to their suitability for use or performance.’

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

3. Specification

The 1152 gearbox has been designed for use in Sportscar endurance and sprint

races, using many existing tried and tested parts packaged to suit the specific needs

of high duty Sportscar formulae. The unit is a longitudinal transaxle design for use in

rear wheel drive vehicles and comprises six forward gears plus reverse.

Xtrac Part Description: Longitudinal Transaxle Gearbox

Assembly

Xtrac Part Number:

1152

900

000

(LMP3)

1152-900-000* (Generic)

3.1. General Items

Drive is transmitted from the engine, through the clutch shaft directly to the

longitudinally mounted layshaft. The layshaft drives the mainshaft through the

change gear ratios. The mainshaft gears are mounted on hubs on the mainshaft and

transmit drive to the shaft itself through sliding dog rings. The mainshaft transmits

drive into the bevel pinion which drives the transversely mounted bevel wheel. The

bevel wheel in turn drives a Salisbury type plate differential. CV-type output flanges

drive customer-specified CV joints and driveshafts.

The change gears are non-synchromesh using 6 flat top dogs, engaged using a full

length barrel. The cluster can be removed as a single unit.

The sequential gearchange operates in the following sequence R, N, 1, 2, 3, 4, 5, 6.

For use in LMP3, the gearbox is rated at ~ 540Nm (400 lbf.ft) input torque *(see note

below).

For use outside LMP3 and fitted with the option uprated cluster and bevel set, the

gearbox is rated at ~620Nm (457 lbf.ft) input torque *(see note below).

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

Casings

The casing material is Aluminium L169 and all casings

have o-ring face sealing.

Change Gears

Six gears with optimised tooth width (gears 1

- 6

have

a gear width of 17.55mm). The gears are mounted on

3.523” (89.484mm) centres, with 1st & 2nd input gears

integral with the layshaft. For more details see Appendix

H – Ratio List-1152B–LMP3 and Appendix J – Ratio List-

1152–Generic.

Final Drive

Bevel Set

High efficiency hard cut cyclo palloid spiral bevel set

(LMP3 standard) or option full form ground spiral bevel

set. 11:31 ratio is standard fitment for the 1152 gearbox.

Differential

Salisbury plate type with fixed preload fitted as standard.

A choice of fixed ramp angles is available.

Output flanges

To suit 108mm 6 ball type CV joints.

Oil Pump

A 9mm wide single stage eccentric lobe oil pump is

included to pressure feed the recirculating gearbox

lubrication circuit. For more details see section 4.2 Oil

System.

Weight

64 kg (141 lb) dry weight.

Gearchange Actuation

Xtrac/Megaline P1254 ‘IVA’ pneumatic actuator.

Dowels and Studs

Included for gearbox to bellhousing face.

*The rating figure given is considered an approximation and is dependent on

engine characteristic as well as absolute value. The method upon which

engine torque is delivered through the transmission can vary considerably

depending on the physical engine characteristic, firing order, fuel and spark

strategy, turbo delivery and any traction limiting system that is utilised. The

life and durability of the gearbox internal parts is also considerably influenced

by factors other than engine output characteristics, for example oil type,

operating temperature and operating environment.

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

3.2. Standard Options (no cost)

Clutch Shaft

Designed to suit customer installation.

Gearing

Gear ratios can be selected from the ratio list. See

Appendix H – Ratio List-1152B–LMP3 and Appendix J –

Ratio List-1152–Generic.

Differential Settings

Various fixed ramp angles are available and the number

of friction faces in the plate differential can also be

adjusted. For details see section 4.4 Differential.

3.3. Optional Extras (cost options)

Gear Ratios

Gear ground and Xtrem polished.

Final Drive

Bevel Set

Full form ground and Xtrem polished.

Clutch

Actuation

An AP Racing clutch slave cylinder from the CP6859

family can be supplied fitted to the gearbox.

3.4. Excluded Items

Gearchange Actuator

1254-932-000A Xtrac/Megaline ‘IVA’ pneumatic actuator.

Bellhousing

Assembly

1152-807-000A Dressed Bellhousing Assembly (LMP3

specification) or other.

Assembly Tooling

See 1152-999-000A drawing for a list of assembly

tooling.

Gearbox Mounting

Dowels, studs, bolts etc.

Oil Temperature Sensor

See section 4.2.3 - Sensors for details.

Oil Cooler & Lines See section 4.2.1 - Description for details.

Clutch

Customer supplied.

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

4. Gearbox Operation

4.1. Gearchange Description

Sequential gearchange operated by Xtrac’s well proven and latest technology

‘overlapping’ polynomial barrel. The gears are engaged sequentially R, N, 1, 2, 3, 4,

5, 6. No mechanical neutral/reverse lock out is available, as the lock out will be

enabled by the AGS gear change strategy. The gearbox is also specifically designed

to use Xtrac/Megaline’s P1254 Integrated Valve Actuator (IVA), see below.

4.2. Oil S stem

4.2.1. Description

An internal single stage eccentric lobe style pump, fitted at the rear of the gearbox

and driven by the layshaft, operates as part of a simple re-circulating system. The oil

is picked up through the oil filter within the baffled scavenge area in the rear portion

of the cluster housing. The scavenge area is positioned to provide pickup

independent of car accelerations and reduce the effects of windage. The oil should

be fed to a remote cooler from the oil-out port (-8) and returned using external hose

(not Xtrac supplied) to the gearbox oil-in port (-8). The use of an oil cooler is

recommended when the gearbox is expected to run for extended periods of time or

in ambient temperatures generally greater than 25.0ºC (77ºF). However, the use of a

cooler is also largely dependent on the in-car installation and the extent to which cool

air is allowed to circulate around the outer surfaces of the gearbox casing. The

cooled oil is distributed internally through the dedicated oil feeds within the gearbox.

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

NOTE: If an oil cooler is not fitted, a link pipe should be fitted between the oil out and

oil in fittings to allow the oil to re-circulate and pass through the dedicated feeds.

4.2.2. Dedicated Oil Feeds

There are dedicated oil feeds/sprays to the dog rings, mainshaft gear hub bearings,

pinion & pinion bearings, differential cassette, crownwheel & crownwheel bearings,

reverse idler bearing and the forward-most layshaft bearing. Please refer to drawing

1152-950-100A for a graphical layout of the oil system.

All other components are adequately lubricated from the ‘splash’ lubrication of the oil

inside the gearbox.

4.2.3. Sensors

Provision has been made for an oil temperature sensor. A temperature sensor

(customer supply) can be positioned on the rear of the gearbox where a M12 x 1.5

thread is provided. Xtrac recommend using the Bosch NTCM12 temperature

sensors, see section 10 Appendix D – Electrical Component Data Sheets.

4.2.4. Filtration and Magnets

A steel mesh filter (125 micron (0.005”) gauze size), which is easily accessible from

the rear of the gearbox can be readily checked to reveal any evidence of tooth/dog

damage and replaced accordingly. If there is a build up of debris, the filter MUST be

replaced for a new one. Note that the flow of oil through the filter is inside to outside,

so any debris will be found inside the filter and not on the outer surface. The oil drain

plug has an integral magnet which will attract and retain debris. This can also be

used as an indication of tooth/dog wear.

4.2.5. Setup/Running Conditions

Oil Type Xtrac XL1 or any other fully synthetic SAE

75W90 gear oil

Oil Quantity 1.6 litre + line/cooler volume

Optimum Sump Temperature 90 - 110°C (194 - 230°F)*

Minimum/Maximum System Pressure Minimum 0.5 Bar/Maximum 1.9 Bar

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

*The gearbox oil must be allowed to reach a minimum sump temperature of 60

Degrees C (140 Degrees F) before full torque is applied, to ensure maximum

durability of the gearbox. Highly loaded running of a cold gearbox is not

recommended due to the risk of premature bearing failure caused by the

additional preload applied from cold casings.

The gearbox oil can be preheated by running of the powertrain with the vehicle

on stands, the use of an external oil heater or an oil-to-water cooler connected

to the engine cooling system. Where these systems are unavailable, it is

imperative that the vehicle is driven in a sympathetic manner until the

minimum gearbox oil temperature is reached.

4.3. Gear Cluster

The 1152 gear cluster comprises straight cut, hobbed and/or ground gears mounted

on the easily removable rear cover subassembly, shown in Figure 1 - Section View

of Gear Cluster Assembly. The gearchange operation is a ‘dog’ type.

Figure 1 - Section View of Gear Cluster Assembly

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

The gear cluster comprises:

•A layshaft with integral 1st & 2nd gears. All other drive gears are slide on. Note

the ‘overlapping’ gear order ‘1st, 2nd, 3rd, 5th, 4th, 6th’.

•Mainshaft with 6 mainshaft gears on 3 hub assemblies plus a reverse gear on

the reverse hub assembly.

•A single, full length barrel with 3 change gear selector forks and a reverse

gear selector fork, mounted on a selector rail.

Drive is transmitted from the clutch shaft directly to the layshaft, driving all layshaft

gears at layshaft speed. All mainshaft gears are in permanent mesh with these gears

but are not coupled to the mainshaft. The reverse mainshaft gear is in constant mesh

with the reverse idler gear (mounted in the maincase), which itself is in constant

mesh with the integral input reverse gear on the layshaft. A dog ring is engaged with

the selected mainshaft gear by a selector fork, transmitting drive from the gear to the

dog ring, through the hub and into the mainshaft itself. The entire cluster can be

removed as one assembly from the rear of the gearbox (as installed) for ease of

inspection and maintenance. The barrel should be shimmed to ensure it holds the

selector forks and dog rings central to the gear cluster. A cluster setting jig (1152-

999-006A) is available for this operation after gearchange barrel and/or barrel

bearing replacement. It is essential that this is checked periodically. Please refer to

the assembly procedure given in section 5.2.2 - Selector Barrel Setup. In addition,

the dog ring and mainshaft gear dogs should be checked and replaced if the dogs

show signs of damage, in order to avoid inconsistent gear changes and further

damage to other systems. Refer to Appendix B – Dog Damage Sheet for guidance.

4.3.1. Reverse Gear

Care should be taken when engaging and driving in reverse gear. Whilst the reverse

gear engagement mechanism is via a dog ring (constant mesh gear train), the

gearbox layshaft speed should be allowed to reduce to 500rpm maximum before

reverse gear is selected and engaged. An engine output torque limit of 150Nm

should be applied whilst driving in reverse gear.

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

4.4. Differential

4.4.1. Description

The gearbox is fitted with a Salisbury-type plate differential as standard, shown in

Figure 2 – Section View of Pate Differential Assembly. The side gears are axially

supported by thrust washers and do not react against any locking part of the

differential. The differential is locked by axial ramp forces through two symmetrical

friction plate packs, giving the differential very linear and predictable locking

characteristics. The side gear rings (ramps) act against a matching cross pin when

drive/coast torque is applied to the differential. The side gear pinion mates are free to

rotate about the cross pin legs independently of the ramp forces. The standard

factory setting for the differential is:-

•60 degree drive ramp angle / 30 degree coast ramp angle

•4 friction faces per side (8 in total)

•48-90Nm static positive preload (new)

An example locking torque vs. input torque plot and table of differential locking

variables can be found in Appendix F – Differential Characteristics.

Figure 2 – Section View of Pate Differential Assembly

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

4.4.2. Ra p Angles

A number of ramp angle combinations are available for the differential. Note that a

corresponding cross pin is also required. The following combinations are given in

Table 1 - Available Ramp Angles.

Table 1 - Available Ramp Angles

Available Angles

Side Gear Ring

s (Ramps)

Cross Pin

45/30 00P-183-0004 & 00P-183-0005 183-0006

55/45 00P-183-0019 & 00P-183-0020 183-0021

60/30 00P-183-0013 & 00P-183-0014 183-0021

75/45 00P-183-0016 & 00P-183-0017 183-0018

Note: Lower ramp angles give higher locking values. The first value specifies drive

and second value specifies coast. (i.e. 60/30 = 60˚ drive and 30˚ coast). However,

the ramps can be fitted in reverse if preferred, e.g. ramp angle of 55/45 fitted in

reverse would give 45˚ drive and 55˚ coast.

4.4.3. Nu ber of Friction Faces

The number of friction faces in the differential can be adjusted from 2 to 4 faces per

side, in order to produce different locking gradients. The number of friction faces

must be kept equal on each side of the differential cassette to ensure the differential

has symmetrical characteristics for right and left hand corners.

4.4.4. Positive Preload

Two ‘belleville’ disc springs are used in the differential cassette to provide a static

axial ‘preload’ through the plate pack, across the differential. The preload value is not

adjustable and will vary between 48-90Nm on build (new) within the manufacturing

tolerances of the differential components. For guidance on differential build, please

refer to assembly drawing 1152-949-000A.

4.4.5. Differential Test Rig

As part of Xtrac’s research and development department, we have developed the

Quasi-Transient Differential Test Rig (QT-DTR) which enables testing of mechanical

plate and Viscous Combined Plate (VCP) type differentials. The differential can be

subjected to varying levels of input torque and differential speed to study the locking

characteristics of available configurations. The following rig operational modes are

available:

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

•Manual operation.

•Sequence testing which will result in a differential characteristic map.

•Quasi-transient testing, a combination of closed/open-loop testing within a

time domain to analyse differential response.

Output data is available in various recognised formats. The data recorded in the test

can then be used to accurately set up the differential to best suit the customer

needs, significantly reducing track testing time.

The QT-DTR is available for rental use on a daily basis including Xtrac technician

support. Xtrac will design and manufacture the appropriate tooling to mount the

customer’s differential onto the rig and, in conjunction with the customer, determine

the most appropriate test strategy and procedure. Testing is then undertaken and a

fully documented results package is available as required. For more information or to

arrange testing, please contact your business manager.

5. Gearbox Assembly and Maintenance

5.1. General Assembl Notes

Only genuine Xtrac parts should be used when overhauling the 1152 gearbox. Key

steel components manufactured by Xtrac are made with our own specification of

steel, either X36C or XVAR1. All Xtrac components are manufactured to our own in-

house quality standards and are inspected at multiple stages of manufacture.

It is good practice to replace all lip seals and k-nuts after removal. O-rings, the oil

filter, circlips and bearings can be reused, but they must be inspected regularly and

replaced as soon as any sign of wear or degradation is evident. A consumables kit

1152-981-005A is available, containing all o-rings, seals, nuts and washers which

should be replaced on a regular basis when carrying out a scheduled inspection.

Lightly oil the parts before assembly and do not use any lubricants other than those

stated in this manual.

The oil filter fitted to the 1152 gearbox must be replaced at least every 6000km

(3728 miles) or sooner if debris has started to collect. The filter is situated on the

suction side of the pump, so any blockage will manifest as a reduced pressure in the

feed lines to the gearbox oil feeds/sprays.

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

Lint free cloths are recommended for wiping down internals. If paper tissue is used,

care must be taken to ensure fibres are not left behind which will result in a blocked

oil filter.

All joint faces are sealed with o-rings, Silicon sealant MUST NOT be used anywhere

on the gearbox, as excess sealant can enter the oil system and clog the filter or oil

sprays around the gearbox. This will lead to premature failure of the transmission.

All components are supplied from Xtrac as "ready to fit". Extra polishing and fettling

of components is not required and may, in the case of gearchange components,

cause failure to other parts, especially gear dogs and dog rings.

Since bearings have press fit tolerances, always heat the casings for the fitment or

removal of bearings to avoid damage to the bearings or casings. Do not heat the

gearbox casings above 135 °C (275 °F.) when fitting bearings as this will weaken the

casting material. Xtrac recommend the use of an oven to control the temperature

and to ensure the heat is distributed evenly. Fit bearings promptly, after removing the

casing from the oven to avoid extra heating cycles being required.

5.1.1. Torque Settings

If not stated on specific build sheets or assembly drawings, all fasteners in the

transmission should be tightened as per the Xtrac Standard XS036 given in

Appendix M – Xtrac Standards. Any non-standard tightening torques are listed in

Appendix A – Non Standard Tightening Torques.

Studs should be inserted tight into the casting using Loctite 270 thread locker. They

must then be allowed to cure for 1 hour at room temperature before further

assembly.

Bolts must either be inserted with Loctite 270/272 (when internal) or be inserted with

Loctite 241 (when external) and wire-locked, unless otherwise stated.

At each build, mark the torque tightened position of all nuts, bolts and screws, by

applying Torque Seal across the fixing and stationary part, to indicate any loss of

tightness or movement, thus avoiding unnecessary spanner checks, which can lead

to over tightened fasteners and stripped casing threads. An example of the use of

Torque Seal is shown in Figure 3 - Correct Application of Torque Seal.

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

Figure 3 - Correct Application of Torque Seal

5.2. Cluster Setup

The cluster should be assembled referring to the Xtrac assembly drawings 1152-

902-000A and 1152-996-000*, in conjunction with the instructions presented here.

5.2.1. Ratio Change Procedure

The instructions presented below describe the simplest method of changing a gear

ratio set.

1. Remove the 1254-932-000A Xtrac/Megaline ‘IVA’ pneumatic gearchange

actuator from the rear of the gearbox, by loosening the 2off M6 k-nuts, and

stow the unit safely.

2. Remove the cluster cover assembly from the gearbox, by loosening the 11off

M8 k-nuts and using the two M6 X 1.0 jacking threads if required. Secure the

1152-499-008A Shaft Holding Tool (as part of the tooling assembly 1152-999-

005A) in a vice and place the cluster cover assembly on the holding tool,

rotating the layshaft and mainshaft as required so their respective splines

engage with the holding tool.

3. Remove the 1152-903-000A Pump Housing Assembly from the cluster cover

assembly, by loosening the 9off M6 k-nuts and using the two M6 X 1.0 jacking

threads if required. Store the pump housing assembly safely aside.

4. Remove the two circlips inside the layshaft and mainshaft locking nuts and

remove the splined lock rings. Loosen both locking nuts in turn, using the 199-

499-004A Gearbox Assembly Socket (as part of the tooling assembly 1152-

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

999-005A) and a 5/8” Hex Drive (1/2” Square). Do not fully remove the locking

nuts at this stage.

5. Lift the cluster cover assembly from the 1152-499-008A holding tool and place

it cluster plate down on the 1152-999-004A Cluster Stand Assembly. The

layshaft and mainshaft locking nuts can now be removed by hand from their

respective shafts.

6. The mainshaft should be withdrawn from the top of the assembly, leaving the

mainshaft assembly components stacked on the cluster plate. Loosen the

selector rail by holding on the two flats at the top end and turning anti-

clockwise. Pull the selector rail out and place aside.

7. The hub assemblies can now be lifted off the stack as necessary in order to

access the gear ratio set to be changed. The layshaft can also be withdrawn

in a similar way to the mainshaft, in order to aid disassembly.

8. Once the gear ratio set has been swapped, reassembly is in the reverse order

as points 1-7. Note the ‘overlapping’ gear order ‘1st, 2nd, 3rd, 5th, 4th, 6th’ and

ensure that all selector forks locate inside the respective tracks on the

gearchange barrel, before the selector rail is refitted.

5.2.2. Selector Barrel Setup

The tolerance stack up on individual parts across the cluster assembly can affect the

position of the dog rings, relative to the mainshaft gears. The gearchange barrel

should therefore be shimmed to ensure it holds the selector forks and dog rings

central to the dogs of the mainshaft gears. The alignment needs to be checked and

altered when a new barrel, barrel bearings or mainshaft assembly is fitted to the

gearbox. Xtrac can offer more advanced training on the following procedure. If help

is required during setup please contact your business manager.

1. With the cluster assembly complete and fully assembled onto the cluster

plate, mount it onto the 1152-999-006A Cluster Setting Assembly and clamp

in a vice.

2. Rotate the barrel to each ‘in gear’ position using the 1152-499-010A Barrel

Socket and measure the dog stand off using feeler gauges, as shown in

Figure 4 - Measuring Dog Stand Off. The dog stand off is the distance

between each mainshaft gear dog root and the tip of the dog ring dog. A small

Issue 2.0 – 10/12/15 - 1152 Longitudinal Transaxle Sportscar Gearbox Manual

2015 - Xtrac Limited, Gables Way, Kennet Park, Thatcham, Berkshire. RG19 4ZA.

Xtrac Inc, 6183 W. 80th Street, Indianapolis, IN 46278. United States

amount of force should be exerted on the fork (at the selector rail journal) to

remove backlash. Dog stand off values are typically 0.05mm to 0.2mm (0.002”

to 0.008”).

Figure 4 - Measuring Dog Stand Off

3. The dog rings reside between pairs of gears (i.e. 1st and 2nd, 3rd and 5th, 4th

and 6th). If the dog stand off values are consistently biased in a single

direction then the 195-401-014* gearchange barrel spacer should be adjusted

to balance these values. See 1152-902-000A Cluster Cover Assembly

drawing.

4. After adjusting the gearchange barrel spacer (by surface grinding or selecting

a larger size) and re-assembling, check all of the values again to ensure the

change was satisfactory.

Please note that, upon initial assembly, the 105-432-153* gearchange barrel bearing

spacer between the inner races of the two barrel bearings is ground to the same size

as the cluster plate abutment shoulder between the outer races of the two bearings,

and hence requires no further adjustment unless the cluster plate is changed.

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