The following kits are suitable for Toyota Hilux/4-Runner vehicles fitted with the standard alloy case 5-speed transmission as fitted behind 4-cylinder petrol and diesel engines.

The standard 5-speed gearbox is marginal in strength. If you intend using the vehicle for towing or if you are fitting a large capacity engine you should consider upgrading to our heavy-duty 5-speed gearbox or an automatic transmission.

No kits are available to the mate any GM Engines to the Hilux/4-Runner 4-cylinder EFI petrol Automatic transmission.

The bolt patterns are illustrated.

The bellhousing has been designed to accept the Toyota petrol pressed metal clutch fork, clutch fork pivot, clutch fork boot and slave cylinder (mounted on the right hand side). The diesel fork and pivot can be used with the petrol slave cylinder but in both cases a cast iron thrust bearing carrier must be used.

When replacing the Toyota diesel engine a petrol model slave cylinder will need to be purchased. Marks 4WD Adaptors stock these slave cylinders the part number is JB4130.

Clutch Master Cylinder

The original Hilux clutch hydraulics do not enough travel to allow the GM clutch to disengage fully. To overcome this problem Marks 4WD Adaptors have developed a kit that replaces the Toyota Hilux clutch master cylinder with a Land Cruiser master cylinder having a larger bore size.

As the slave cylinder for the diesel models is located on the left-hand side of the vehicle and the new bellhousing has the slave cylinder on the right side the hydraulic pipes will need to be shifted and modified to suit. Alternately Marks 4WD Adaptors can now supply a crossover pipe comprising of braided stainless hose, hose fittings, and other mounting hardware to do the job with a minimum of fuss.

We recommend using a GM 10" or 10.5" pressure plate with a Toyota 10" clutch disc. Marks 4WD Adaptors stock these special clutch kits.

The standard GM flywheel with 153-tooth ring gear must be used.

The GM engine can be fitted to the vehicle without the need to reposition the transmission, modify the firewall, or alter drive shaft lengths.

The standard GM starter motor is used for the conversion.

Engine mounts are available for Holden V8 engine conversion kits. The engine mount brackets have been designed to bolt to the engine block and fit to the Toyota mounting rubbers. 18R, 22R petrol and 2.2, 2.4 and 2.8 diesel engine, chassis posts remain in their original position. All vehicles with independent front suspension or that were originally fitted with 3Y or 4Y engines require new chassis posts.

The standard Toyota radiator is not large enough to keep the Holden V8 engine cool. We recommend using a Heavy Duty Holden HQ radiator with modified bottom tank to allow the radiator to sit down between the chassis rails. To fit this radiator you will also need to modify the radiator support panel. The engine will need to be fitted with a fixed flexi fan and must be used in conjunction with a fan shroud.

When fitting Holden V8 engines to Toyota Hilux/4Runner vehicles with leaf or independent front suspension the engine oil pan will need modification to clear the front differential, drive train and in some cases the steering.

Marks 4WD Adaptors manufacture a new oil pan/sump to fit Holden V8 engines in Toyota Hilux/4Runner leaf sprung vehicles. This oil pan/sump is designed to give legal differential and steering arm clearance. The oil pan fits in front of the differential housing and the steering arm linkages. The sump/oil pan holds approximately 5.5 litres / 1.2 gallons of engine oil and is supplied with a new oil pickup.

When fitting Holden V8 engine the hand brake pulley located on the right hand side of the firewall will touch on the back of the cylinder head. Marks 4WD Adaptors manufacture a kit that relocates the handbrake bracket and pulley to the cabin side of the firewall.

When fitting a Holden V8 engine some brackets will need to be fabricated to fit the Toyota A/C compressor and power steering pump to the new engine.

The wiring of an EFI engine can be a daunting task especially if you have no prior experience with electronics. well fear not because Marks 4WD Adaptors have an interface wiring loom which is fitted with the EFI, fan, A/C, fuel pump relays, and fusses along with the original GM plugs that correspond with the engine loom. The few remaining trailing wires are labelled to show you where to connect them.

The standard Toyota petrol tachometer will not operate directly from the V8 ignition system. Marks 4WD Adaptors manufacture an interface for the V8 petrol engine that will make operative the original 4-cylinder tachometer.

At the present time no tacho interface is available for the Diesel Toyota tachometer.

Commodore V6 and V8 vehicles are fitted with with a diagnostic test light to alert the driver of electronic component failure associated with the engine management system. Marks 4WD Adaptors manufacture a diagnostic test light, switch and loom that can be fitted into any vehicle fitted with a Commodore V6 or V8 engine requiring simple and quick engine management diagnostics.

Vehicles previously fitted with carbie engines are commonly being re-powered with Commodore, Chevy, and Oldsmobile EFI V6 and V8 engines.  When the vehicle was fitted with a carburettor no problems were experienced as the carbie bowl acted as a reservoir and prevented fuel starvation. Unfortunately EFI engines rely on constant fuel pressure for the injectors to operate properly. In a lot of cases the fuel tanks are not equipped with baffles that prevent fuel starvation when accelerating quickly or climbing steep hills, the fuel supply line in some cases is also to small for the high volume high pressure pump.

To over come this problem Marks 4WD Adaptors manufacture a surge tank that is used in conjunction with a low pressure lift pump. The lift pump is mounted on the side of the surge tank, it transfers fuel into the surge tank which holds approximately 1ltr of fuel. When it's full, an over flow pipe caries the excess fuel back to the fuel tank.

A 12mm outlet is fitted in the top of the tank allowing unrestricted fuel supply to the high pressure fuel pump, the 12mm outlet is fitted with a pickup tube which is suspended approximately 25mm from the bottom of the surge tank. This allows heavy material and water to be separated from the fuel, a drain plug is fitted for ease of servicing. The return fuel from the engine is plumbed into the top of the surge tank through a separate fitting.

The tank is supplied with all fittings, lift pump, mounting bracket, hardware and instructions.

For the Commodore ECM/PCM to function properly and allow the engines emissions to comply with EPA regulations it must acquire a speed signal from the VSS. Marks 4WD Adaptors manufacture a number of VSS units and VSS interfaces to suit most EFI engine and vehicle combinations.

Vehicles previously fitted with engines that ran on either Diesel or Leaded Petrol are required to have a ULP restrictor fitted to the filler neck of the fuel tank. A ULP restrictor from a later model or unleaded vehicle  can be purchased from your local wrecking yard and fitted to your vehicle.