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13 Miscellaneous items

13-1 Engine and transmission

Reasons for rejection


1. The engine or gearbox is insecurely mounted.

2. A driveshaft is bent or severely damaged.

3. A driveshaft flange:

a) is insecure, or

b) has a bolt or nut missing.

4. A driveshaft support bearing is:

a) insecure, or

b) worn beyond manufacturer’s specifications.

5. A driveshaft universal joint spider (cross) bearing:

a) is worn so that the movement in the joint is beyond manufacturer’s specifications, or

b) caps have loose or missing cap bolts or circlips, or

c) is damaged, displaced or the seals between the spider journals and bearing caps are missing.

6. A rubber doughnut-type driveshaft coupling:

a) is worn or damaged beyond manufacturer’s specifications, or

b) is split or delaminated so that its mechanical integrity is affected, or

c) securing bolt is loose or missing.

7. A driveshaft slip joint (spline) is worn beyond manufacturer’s specifications.

8. The universals in the driveshaft are not fitted in accordance with manufacturer’s specifications.

Modifications (see also Introduction 3.1.2: Note 3)

9. A modification (Note 1) affects the engine and transmission (Note 2), and:

a) is not excluded from the requirements for LVV specialist certification (Table 13-1-1), and

b) is missing proof of LVV specialist or accepted overseas certification, ie:

i. the vehicle is not fitted with a valid LVV certification plate (Note 3), or

ii. the operator is not able to produce a valid modification declaration or authority card , or

iii. the vehicle has not been certified to an accepted overseas system as described in Technical bulletin 13 .

Note 1 Definitions

Modify means to change a vehicle from its original state by altering, substituting, adding or removing a structure, system, component or equipment, but does not include repair.

Repair means to restore a damaged or worn vehicle, its structure, systems, components or equipment to within safe tolerance of its condition when manufactured, including replacement with undamaged or new structures, systems, components or equipment.

Note 2

LVV certification is always required for the fitting of a supercharger or turbocharger as a modification, or the upgrading of a supercharger, turbo or wastegate, or the re-chipping of electronic engine control units on turbo vehicles.

Note 3

Where an LVV certification plate has the engine type as ‘MOD’ after the make (eg Nissan MOD), that certification can cover a wide range of modifications, including aftermarket or modified wastegates, larger or modified turbochargers, re-programed ECU’s, and many other performance enhancements commonly fitted to a wide range of vehicles.

If presented with a vehicle with an engine modification and ‘MOD’ on the certification plate, assuming all other certification plate details match and all WoF requirements have been met, a WoF can be issued.

Note 4

Externally venting wastegates (screamer pipes) are not permitted and cannot be certified as they are not adequately muffled and the exhaust gasses do not exit behind the passenger compartment. However, wastegates that feed gasses into their own muffled exhaust system exiting behind the passenger compartment, or feed gasses back into the vehicle’s exhaust system, are permitted.

Table 13-1-1. Modifications that do not require LVV certification

Fitting of or modification to:

LVV certification is not required provided that:

Substitution of engines

  • when compared with the OE engine, the replacement engine:
    • is of the same or less cubic capacity, and
    • has equal or less weight, and
    • uses the same fuel (petrol, diesel, LPG, CNG), and
    • uses the same unmodified attachment points and system (i.e. bolts-in), and
    • uses the same family of block and cylinder head from the same vehicle manufacturer, and
    • the block has the same number of cylinders arranged in the same configuration, and
    • the head has the same number of valves and camshafts, and
    • meets the requirements of minor modifications detailed below, and
    • when the minor modifications have been taken into consideration the total power or torque increase is no more than 20% over the OE engine specification.

Minor modifications to OE engine

  • the total modifications (including engine substitutions) are minor, resulting in no more than a 20% power or 20% torque output increase over the OE engine specification.

Note that common minor modifications include the fitting of:

  • extractor or free-flow exhaust manifolds, or big bore exhaust systems
  • changed intake manifolds
  • changed or multiple carburettors
  • modified fuel injection systems
  • changed ignition systems
  • alternative cold air box induction systems.

Note that minor modifications DO NOT include:

  • fitting of a supercharger, or
  • fitting of a turbocharger, or
  • upgrading/modifying the supercharger, or
  • upgrading/modifying the turbocharger, or
  • upgrading/modifying the wastegate, or
  • tuning/re-chipping (Note 5) the ECU of a turbocharged or supercharged engine, or
  • single camshaft to twin camshaft, or
  • carburettor to injectors, or
  • injectors to carburettor, or
  • stroker kit, or
  • any other capacity increase that exceeds usual reconditioning.

Gearbox substitution

  • the OE gearbox cross-member has not been heated, cut or welded,
  • the OE gearbox cross-member mounting to the OE body or chassis members is unchanged,
  • no replacement gearbox cross-member is used,
  • the OE driveshaft(s) is unmodified,
  • no substantial modifications have occurred to the floor or gearbox tunnel area, other than provision for gear-shift mechanism,
  • the braking system is not modified or changed, including the brake pedal.

Change from 4WD to permanent 2WD (removal of drive train components in 4WD vehicles)

  • the vehicle was originally manufactured with selectable 4WD and a solid/live front axle.

Fitting of or modification to:

LVV certification is never required:

Any modification for the purposes of law enforcement or the provision of emergency services

  • in-service requirements for condition and performance must be met.
Note 5

Tuning/re-chipping includes any software or hardware (ECU or piggy back system) change that is intended to alter the fueling, boost pressure or ignition timing from the OE specifications.

Figure 13-1-1. A typical driveshaft assembly

Figure 13-1-1. A typical driveshaft assembly

Summary of legislation

Applicable legislation
Condition and performance

1. The vehicle must be safe to be operated.

2. The components and materials must be fit for their purpose and within safe tolerance of their state when manufactured or modified.


3. A modification that affects the engine and transmission must be inspected and certified by an LVV specialist certifier, unless the vehicle:

a) is excluded from the requirement for LVV specialist certification (Table 13-1-1), and

b) has been inspected in accordance with the requirements in this manual, including those for equipment, condition and performance.

Page amended 1 October 2020 (see amendment details).