TO

Chevy V8 Diesel Engines

Nissan GQ/GU Automatic Transmission

Marks 4WD Adaptors manufacture conversion kits to replace the standard Nissan TB42, TB45 and TB48 petrol, TD42 and ZD30 diesel engines with GM diesel V8 engines.
The 4-speed automatic transmission fitted to these vehicles is very durable however performance upgrades will be required for it to satisfactorily handle the power and torque of a V8 diesel engine. The 5-speed automatic transmission is not preferred for this engine conversion as the electronics required to make it perform correctly are not readily available. We would recommend you fit a GM 4L80E automatic transmission in place of the original 5-speed auto when fitting a Chevy diesel engine in place of the 4.8ltr engine.

To enhance your vehicles off road performance and safety we recommend you fit a set of extra low range gears

Engine Kit
The kit consists of an adaptor housing which couples the new engine to the original petrol or diesel bellhousing. The new adaptor housing measures 72 mm in length and spaces the Chevy engine away from the irregular shape of the Nissan Patrol firewall.

No firewall modifications or re positioning of the original transmission is required.

The automatic transmission is retained in its original location along with the original torque converter and flex-plate.

A specially machined crankshaft adaptor supplied with the kit bolts to the rear of the GM engine and flywheel. The adaptor converts the rear crankshaft bolt pattern from GM dimensions to standard Nissan 6 bolt crank dimensions allowing the Nissan flex-plate and torque converter to be connected to the engine.

A standard GM flywheel is needed for the conversion. The GM automatic flex-plate is not used as the ring gear can be pushed away from the starter pinion while cranking.

An adaptor housing cover plate, which protects the bottom of the automatic transmission from water and dust entry, as well as all the required bolts, nuts and washers are also supplied with the kit.

An oil pressure sender adaptor is supplied in the kit. The adaptor allows the original Nissan sender to be fitted to the Chevy diesel engine. A water temperature adaptor is also supplied in the kit. This adaptor allows the original Nissan Temperature gauge sender to be fitted to the Chevy diesel engine.

Chevy Diesel Air Cleaner Adaptor

Chevy diesel engines are usually fitted with an air cleaner that looks similar to the type fitted to Chevy petrol carburettor engines. This type of air cleaner will require modifications to allow it to be used with a snorkel. To over come this problem Marks 4WD Adaptors now manufacture a cast aluminium hat that takes the place of the GM air cleaner, this cast hat can then be easily connected to a Donaldson or similar type air cleaner via its 3 1/2" inlet.

Engine Mountings
Engine mounting kits are also available to fit the GM V8 engines. These kits consist of engine mounting rubbers, bolts, and new chassis brackets. The old chassis brackets will need to be cut off the chassis and the new ones welded back on. The engine mountings have been designed to give you sufficient legal sump to differential clearance when using a rear bowel GM sump.

NOTE: The engine mounting kits will only suit coil sprung front-end vehicles. Early cab chassis GQ and Ford Maverick vehicles were fitted with leaf springs.

Engine Mounting Rubbers
Two types of engine mounting rubbers are available, standard Chevy type and now a heavy duty rebuildable type using urethane bushes. Click here for details.

New Chevy Bolt In Engine Mountings
We now manufacture engine mounting brackets that bolt directly from the engine block to the original Nissan engine mounting rubbers.

Front Springs
Heavy-duty front springs are recommended with a 25mm bump stop extension, this is required to give adequate front drive shaft to adaptor housing clearance. A 25mm bump stop extension is included in the kit.

Fan Adaptor
An efficient cooling system requires a good radiator, engine driven fan and fan shroud, the GM and Nissan viscous coupled fans are not as effective as the Toyota type. Marks 4WD Adaptors now stock Toyota viscous couplings and fan blades, we also manufacture an adaptor that couples the Chevy V8 diesel water pump and pulley to the Toyota viscous coupling and fan.