"Project 100#" Cruiser Gearbox Rebuild



Rebuilding 4WD Gearboxes at Gympie 4WD Spares
Welcome to the first instalment of  our Gympie 4wd "Project 100 series" video series. In this 9 part series we are rebuilding the gearbox for the 100# Landcruiser.

We specialise in supplying reconditioned exchange transmission and diffs for your 4wd, and we wanted to give you guys a inside look at how we recondition our gearboxes in-house.

Scroll down to the bottom for easy links to the video series . . .


Drivetech 4x4 Gearbox Rebuild Kits

This Landcruiser H151 gearbox has just on 300,000klms on it, and with the addition of the factory turbo diesel to the our Project Landcruiser, we’ve decide to go through the gearbox to make sure it’s a reliable unit for many years to come.

You will see Dale strip down the gearbox and disassemble the components to assess the condition of the internals. He is checking for wear and examining every piece of our gearbox puzzle.

Gympie 4wd Spares can supply all the parts you’ll need to rebuild your own transmission or diff. We use Drivetech 4x4 components - Drivetech 4x4 is one of Australia's leading 4wd spare parts suppliers - and they've been around long enough for us to be more than confident using their parts in a rebuild. (We have a six month warranty on our rebuilt gearboxes and diffs - so this is really important!) Their massive catalogue ranges from transmission parts to their ever-increasing range of 4WD accessories.

This particular gearbox out of our Project 100 Series will require a full rebuild kit, new cluster gear shaft, input gear shaft, 5th gear, and all new synchros.

In addition to reconditioning the gearbox, the transfer case has also been reconditioned, with the added components of the "Marks 4WD Adaptors" part time conversion kit. This changes the 100# Landcruiser from a full –time 4wd to a part-time 4wd, prolonging the life of the front end drivetrain components and improving the handling of the vehicle.

4wd Gearbox mainshaft

Throughout this video Dale will assemble the mainshaft and its components.
All of the parts used in this video have been supplied by Drivetech 4x4.
Gympie 4wd Spares is a Platinum supplier for Drivetech 4x4 and stock a huge range of spares, accessories and hard parts - instore and online.

4wd main shaft and cluster shaft assembly

Drivetech 4x4 Filter kits, rebuild kits, suspension, led lighting, recovery equipment - all available at our online store - Ez4x4.com.au.

Drivetech 4x4 Gearbox Rebuild Kits

The H151 Toyota gearbox is the perfect match for the Landcruiser 100# - big gears and big bearings to handle the loads we throw at them in Australia.
The H151 gearbox is found in all 80 series, all FZJ105 and HDJ100s and the factory 6 and 8 cylinder turbo Landcruiser utes.

Particular care is taken when assembling the synchronising rings to the synchroniser hubs and gears – the most common problem we see with this style of gearbox is gear changing issues.

H151 Landcruiser Gearbox

Dale now prepares the cluster or layshaft. The input to mainshaft requires 14 individual bearings which Dale inserts into the input shaft using assembly lube to retain them in place during assembly.

Dale now begins assembling the main shaft and cluster shaft to the sandwich plate. This will form the chassis of the transmission.
Throughout the assembly of transmissions, assembly grease and oil is used to help lubricate the components during the process, and also protect the surfaces until the assembly is put in use.

4wd main shaft and cluster shaft assembly

These cast alloy selector forks are pushed back and forth by the selector shaft, sliding the selector sleeves over the selector hubs and synchros. You can see in this clip the detense and lockouts are inserted into the sandwich plate – these help retain gears in position and also eliminate the possibility of selecting two gears at once.

4x4 select shafts
4wd gearbox casing assembly

The casings are now ready to be assembled to the chassis. The alloy casings are an integral part of the gearbox. They retain bearings, contain the lubricants and provide the strength and rigidity for the immense loads occurring inside.
All external fixings are then fitted – front retainer plate, selector housings etc.

The H151 holds only 2.5 litres of oil, and relies on the mainshaft to drive an oil pump which is located in the rear housing. Benchtesting is obviously an important step in the process – checking the operation of all the gears and synchros.

Installing the rebuilt gearbox

Now the reconditioned gearbox is bolted on to the transfer case – the transmission jack makes the boys job a lot easier. This gearbox/transfer combo tips the scales at just over 110kg.
For this rebuild we’ve fitted a 4-Terrain Heavy Clutch from the guys at Clutch Industries. Check out their clutches – they offer superior strength in an extra heavy duty clutch, but without the heavy pedal other clutches can have.

So there you have it - our in-house reconditioning process at Gympie 4WD Spares.
Give us a call on FREECALL 1800 072 099 if you have any questions about our reco 4x4 gearboxes and diffs.

Stage 1
Stage 2
Stage 3
Stage 4
Stage 5
Stage 6
Stage 7
Stage 8
Stage 9

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