Major Service

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Overview of the VR-4 Major Service

The major service on the VR-4 is considered to be the biggest and most complex service with the following details:

Frequency Core Tasks Optional Tasks
Every 100,000km Replace Timing Belt

Replace crankshaft oil seal

Replace Water Pump

Replace Coolant

Replace Timing Belt Tensioner

Replace Timing Belt Tensioner Pulley

Replace camshaft oil seals

Replace harmonic balancer

Replace alternator belt

Replace AC/Power steering belt

Bleed Brakes

Replace Transmission/ATF fluid

Bleed Clutch

Replace Transfer Case fluid

Required Tools

The tools you will need for the major service will depend on whether you are performing just the core service or all of the optional tasks. We list the tools here for each, plus alternative tools (where possible) if you do not have the recommended tool.

Tools for Core Tasks

Tool Purpose Alternatives Notes and examples
1/2" socket set Removal of various bolts Spanners (if you're a mad lad). Socket set will need to include 10mm through 17mm, and 19mm through 21mm.
3/8" socket set Removal of various bolts in the harder to reach places Spanners or trying to do it all with a 1/2" socket set Used to access tighter areas.
Open and ring spanner set Removal of bolts and nuts that cannot be reached with sockets, or holding nuts on the other end of bolts you are removing with the socket set.
Camshaft sprocket holder Inserting into the two guide holes to hold the crankshaft pulley (harmonic balanacer) while you remove the bolt. Breaker bar inserted into harmonic balancer bolt head, followed by tickling the starter motor Whilst this is a cam sprocket holder, the 6A13 harmonic balancer has two guide holes that allow use of this type of tool. The Mitusbishi service manual specifically mentions tool MB990767 and the right size pins (MD998754) for holding the pulley. Most generic tools come with multiple size pins.
Example of a generic cam sprocket holder
Example of how the crank pulley is restrained with a cam sprocket holder
Very powerful 1/2" impact gun Removal of harmonic balancer bolt Breaker bar If restraining the harmonic balancer using a cam sprocket holder, the impact gun needs at least 1,500Nm of nut busting torque. If you do not have such a tool, you can try a breaker bar.
Small 10mm open ended spanner Removal of the timing cover bolt behind the Power steering pump bracket Removal of the power steering pump bracket before accessing this bolt. Seriously, this one bolt will make you rage.
Timing belt tensioner wrench (socket) Tensioning and holding the timing belt in position so you can then tighten the tensioner pulley cam. A screwdriver and feel. Mitsubishi list this tool as part code MD998767 but these can be purchased from eBay by searching for terms like "Mitsubishi Belt Tension Tensioner Adjuster Pin Wrench Timing Tool".
Example of the timing belt tensioner wrench and where the pins locate in the tensioner pulley

If you don't have access to this tool, you don't need the beam style torque wrench either. In that case you tension the belt by levering the tension of the pulley using a screwdriver braced against the alternator bracket. This is an inaccurate method but likely to result in an over-tight rather than loose belt given the low torque (3Nm) required to tension the belt.

Beam style torque wrench with range of 0-9Nm (must be able to measure 3Nm) For use with the timing belt tensioner wrench A regular style of torque wrench can be made to work but needs to go down to under 3Nm If you don't have access to a torque wrench, use the screwdriver method as above.
Example of a beam style torque wrench (note 0-9Nm range)
Oil seal removal tool For removing the crankshaft oil seal Small drill bit and self tapping wood screw
Example of a generic oil seal removal tool suitable for accessing hard to reach seals.
If you do not have an oil seal removal tool (search eBay for the term "Shaft Type Seal Puller"), you can carefully drill a small hole in the oil seal, screw a self-tapping screw into that hole and then pull on the screw with pliers.


Make sure you do not scratch either the crankshaft or the block where the oil seal mates to.

Gear locks Locking the camshafts in TDC position while you replace the belt. Bulldog clips to hold the timing belt onto the cam sprockets. When replacing the timing belt, you can either use cam locks to hold the cams into position for the entire duration of the work, or you can just:
  1. Hold the cam sprock in position with a ring spanner on the cam sprocket bolt
  2. Slip the new timing belt onto the sprocket
  3. Check that the crankshaft and cam timing is correct
  4. Place a bulldog clip to hold the belt onto the sprocket
  5. Move to the next cam sprocket and repeat steps 1-4
This is the Mitsubishi recommended method in the service manual.
Cam gear locks can also be used, but are not necessary. See example below.
Example of generic cheap cam gear locks

Required Parts

The parts you will require will depend on whether you are performing the core tasks or also the optional tasks.

Parts required for core tasks

In general we recommend you buy a major service kit from one of our recommended vendors, and ensure that the components are high quality. Any failures related to the timing belt assembly or water pump can cause excessive damage or at best require you repeat the service again.

Part Recommendation Notes
Timing Belt
Water pump
Timing belt tensioner pulley
Timing belt pulley
Timing belt idler pulley
Timing Belt tensioner
Crankshaft oil seal
Replacement tensioner pulley bolt Grade 8 strength The factory timing belt tensioner bolt has been seen to fail on multiple vehicles after being re-used during a major service. This failure can and has caused catastrophic engine damage. Ensure to replace this bolt with a Grade 8 by taking the factory bolt to a bolt supplier and obtaining a bolt of the same length and thread pitch.
Coolant Any regular green stuff

Parts required for optional tasks

Part Recommendation Notes
Camshaft oil seals (x4) Removal of the front and rear bank camshaft oil seals is difficult due to lack of space. Ensure you have the shaft style oil seal removal tool or you will struggle greatly.
Harmonic Balancer OEM only
Alternator belt
AC/Steering belt
DOT4 Brake fluid Do not use DOT5. DOT5.1 may be used but is not necessary for street driving.
Automatic transmission fluid
Manual gearbox oil 75w85 synthetic The gearbox uses GL-4 rated oil.
Transfer case oil 75w85 synthetic You must use GL-5 rated oil, not GL-4. The transfer case oil is for lubricating the ring and pinion gear which needs differential oil, not gearbox oil.