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Gaz

Hilux LSD diff identification

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Anyone know how to tell a hilux LSD from numbers on it or cxodes or anything without actually cracking it open or playing with it?

Thanks

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they generally have a sticker with "LSD" attached near the filler bung.

aside form that - vehicle chassis plate. will prolly only give a diff series though. nopt sure on what code it will be.

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on the chassis build plate next to axel it'll have a number like G282

the last digit 2=2pinion open diff. 3=2pinion lsd. 4=4pinion open diff. 5= 4pinion lsd.

g = series of diff

and second number means the ratio.

if its a nz new ones then plate prob wont say sh!t all. the other way i've heard is removing the driveshaft and theres paint on the input flange but i'm yet to see it or a code saying wat they are.

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The diff is already out of the vehicle at a wreakers so chassies code is no good.

Hope the sticker is still on

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basic check (rule of thumb, aplies to all)

turn an axle and the other should go the same way, (as it shouldnt go backwards, thats open wheeler) or hold one axle and try to turn other. it will not be posible by hand.

DONT BE STUPID AND JACK UP ONE SIDE OF A CAR AND DRIVE IT TO SEE IF ITS GOT ONE!

its only for when the diff is out of the car. (had to say)

Ratio is turn driveshaft and count the axle turns. for example, one turn of the driveshaft input will give 4.5 if the axles. high number will have the axles spinning fast (eg 4.111) low number will be low speed (eg 2.5)

Low numbers are best in high torque, low revs engines (eg V8s and deisels) provide great fuel economy, top speed. lose responsiveness.

High numbers are best in low torque, high rev engines(eg 4AGEs, Rotarys ect) provide mind bending acceleration, lose top speed.

thats a realy bad summary, as it depens on gearbox (5sd/6sd) and tyre size. a 215/45R17 has a longer rolling diametre to a 215/45R14. so the smaller tyre is as effective as changing the diff ratio to a higher one.

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What you said is not a valid way to check for an LSD.

I suggest you read here and it will explain why. //oldschool.co.nz/phpbb/viewtopic.php?t=7023

I know how to check for an LSD already if I had the diff.

I want an ID number so I can get someone else who is not mechanically minded to check.

Thanks anywho tho.

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i found this somwhere on the net. it should be helpful to u guys....

Identifying Toyota Hilux & Hiace Differentials

The Toyota Hilux has ID plates fitted in the engine bay, while the Hiace has them fitted near the

base of the front seats. In each case one of the plates will have the 'Axle' code originally fitted to

the vehicle.

As an example a RN25 Hilux manufactured during the 2/74 has the 'Axle' code "G142".

The letter "G" signifies it has a "G" series differential and therefore an 8" diametre crownwheel.

The next two digits, "14", nominate the ratio, which according the ratio table below is 4.875:1.

Many of the ratios have not been fitted to Australian vehicles nor are they all sold here as an

aftermarket item. The 4.875 and above ratio centres have a slightly different crownwheel position

on the centre. So if ratios below 4.875 are to be fitted then select a diff with a ratio below 4.875 or

vice verca if shorter ratios are to be used.

Two suppliers who have crownwheel & pinion sets are Sunstate 4WD & Jack McNamarra Diffs.

The last digit, "2", is for the type of centre, in this case 2 Pinion & Open centre as per the centre

table below. The factory LSD is a clutch pack type, while aftermarket suppliers offer these, plus a

wide range of other types.

RATIO TABLE

Code Ratio

Code Ratio

Code Ratio

Code Ratio

01

3.300

13

4.790

25

4.556

37

3.583

02

3.360

14

4.875

26

5.571

38

3.417

03

3.545

15

5.125

27

3.364

39

3.154

04

3.556

16

5.286

28

4.300

40

5.375

05

3.700

17

5.600

29

4.100

41

3.308

06

3.889

18

5.714

30

3.727

07

3.900

19

5.833

31

3.909

08

4.110

20

6.167

32

6.591 or 4.807

09

4.222

21

6.667

33

7.503 or 5.583

10

4.375

22

6.780

34

6.781 or 4.786

11

4.444

23

6.833

35

7.636 or 5.600

12

4.625

24

7.640

36

4.778

CENTRE TABLE

Code Centre Type

2

2 pinion open centre

3

2 pinion limited slip centre

4

4 pinion open centre

5

4 pinion limited slip centre

The Toyota Hilux & Hiace Differentials

The Toyota Hilux and Hiace differentials are all similar in design. They feature an 8" crownwheel,

31 spline axles and large bearings. They have ample capacity for an Escort and a converted Hilux

diff will weigh about 60kg.

Common ratios to be found at wreckers in Australia are from 4.110:1 to 4.875:1. The taller ratio of

3.7:1 was delivered with V6 vehicles in the USA. Aftermarket suppliers in Australia have gear sets

of 3.5:1, 3.7:1 etc. available new.

The closest fit for an Escort is the Hilux 2WD diff from RN10, RN15, RN20 & RN25 models

manufactured during the first half of the 70's. Each of these has the same spring centres (940mm)

and overall width (1350mm) as an Escort. The spring platform width is equal to the MkII Escort at

60mm but wider than a MkI which has 50mm width springs.

What needs to be modified ?

Axle Shafts and Flanges

These axles have five M12x1.5mm studs on a 4.5" PCD and will require restudding to match the

MkII Escort pattern of four M12x1.5mm studs on a 4.25" PCD. The Hilux studs are longer than

Escort studs. The MkI Escort has 7/16"UNF studs on a 4.25" PCD.

The drum/wheel location boss on the Hilux axle is Ø67mm compared to the Escorts Ø63mm. If

Escort drum brakes are to be used then the boss must be machined down. If an upgrade to larger

drums or disc brakes is chosen then the boss may need changing in size to suit the alternate drum

or disc centre hole.

Some Escort mag wheels may fit over the Hilux boss but standard wheels and some mags will

require the boss to be Ø63mm where it protrudes out further than the drum or disc and into the

wheel.

If alternate discs are fitted over the axle flange this will increase the overall width of the diff by the

thickness of the disc bell on each side of the diff. So if discs with a bell thickness 7.5mm are fitted

then the overall diff width will be 1350+7.5+7.5=1365mm. Check your tire clearance to the guards

and track width requirements. Most of the axle shaft fitted to the RN10-25 models have sufficient

spline length for the axle to be shortened a small without the need for re-splining, but work out

what you need and measure the axles before purchase.

Brakes

The Escort drum brake backing plates will need the centre hole size and bolt pattern changed to fit

over the Hilux bearing carrier. The backing plate will need a spacer behind it so that the drum

properly covers the brake shoes.

Upgrading the brakes to discs has been done and reuse of the Hilux drum system may be possible.

Differential Centre

The ratio and type of the centre that is factory fitted to RN10-25 Hilux may not be suitable or

serviceable considering the age. Options are to fit a diff centre from another later model Hilux or

Hiace that has a suitable ratio or Limited Slip centre for example.

Other options are to fit aftermarket ratios or Limited Slip Differential centres and new bearing and

seals.

If the chosen ratio is different to standard and an accurate speedo is required, the speedo accuracy

will need checking and correcting.

Differential Housing

If Escort drum brakes are retained the handbrake linkage brackets and hydraulic line bracket will

need fitting to the Hilux housing.

If the factory style anti tramp rods are to fitted then these will need fitting to the Hilux housing at

the correct angle relative to the spring platforms.

For originality sway brackets would also need fitting to the Hilux housing at the correct angle

relative to the spring platforms.

If discs, tyre clearance etc. dictate shorter axles then the housing will also have to be shortened by

an equal amount on each side.

With the exception of tramp rods, the brackets can normally be cut from a donor Escort housing.

Shackles and Shackle Plates

The RN10 - 25 Hilux housing axle tubes are Ø65mm and 5.5mm thick compared to an Escort axle

tube at Ø63mm and 3.2mm thick. The Escort shackles fit over this housing, alternatively the

slightly larger diameter Hilux shackles will fit through the Escort shackle plate.

The MkII Escort shackle plates will not require modification to use this Hilux diff housing.

Spring Platforms

To prevent rapid universal joint wear and tailshaft vibration, the operating angles of front and rear

universal joints need to be similar, eg: less that 1° difference in operating angle.

The angle required will varies depending on whether anti tramp rods are fitted and the

curvature/rating/ride height of the leaf springs. Anti tramp rods and stiffer leaf springs reduce the

amount the diff nose lifts under power where as leaf spring curvature and ride height alter the

static position of the diff nose.

The angle of the spring platform to the pinion needs to be checked and altered, if necessary, by

relocating the spring platforms around the axle.

If this diff is fitted to MkI leaf springs, the 50mm wide MkI Escort spring platforms will need to be

fitted to the Hilux Diff.

Tailshaft

The 1 peice Escort tailshaft that has replaceable universals has the same universal as most of the

Hilux/Hiace units, but the tailshaft will need shortening and a Hilux flange fitted to the universal.

Other Hilux & Hiace Diffs

Later Model Hilux 2WD

The later model, particularly 80's on, 2WD hilux diffs are to wide to be useful in an Escort fitted

with wider tyres. The axles do not suit re-splining as they are machined down behind the existing

spline for too great a distance.

They may provide the ratio you are looking for though.

Hilux 4WD

The Hilux 4WD diffs are generally 20mm narrower than an equivalent year 2WD diff. Some of the

axles have an extra length spline that may be shortened without the need for re-splining, in

particular check out the RN46 manufactured around 4/83. All 4WD axles have 6 wheel studs and

can be re-drilled for an Escort stud pattern without the need for welding up the old stud holes.

The 4WD housings are the least suitable as they are step up in diameter toward the centre and will

cause mounting hassles for brackets and shackles.

The 4WD centres will in some cases be Limited slip units and may contain suitable ratios.

Hiace

The Hiace diffs are all to wide for an Escort. The housings are the same style as the 2WD Hilux but

the axle tube dimension is 68mm x 62mm oval and 4.5mm wall thickness. Use of this housing

represents a small weight saving which may be cost effective if the 2WD housing for your

application requires shortening and other alterations.

The Hiace centres may also have the ratio you are looking for.

The mid 90's Hiace is fitted with a wheel stud that has extra spline length. These may prove useful

for a disc brake setup.

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That's great if you have a Japanese assembled Hilux that you are pulling it from, but NZ ones have a different chassis code system

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Yea, this is what I mean, vehicle that were built here don't follow the same code...

Out of interest did the van do a squillion revs at 100?

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This is a jap import

but yeah, 4.87 is a high number.

However its a deseil turbo 2L turbo motor, so hardly a power house, and moving a decent amount of weight

I would say the diff ratio was set up perfect would do 100 but not much more

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