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The Testers Manual

2.4 Suspension - General

Information	Method of Inspection	Reason for rejection
This sub-section applies to Both front and rear suspensions	A. All Suspension Types 1. Check
How to inspect
The inspections must be carried out with the veh ide over a pit or on a raised lift. The examination of some front suspension components requires the steered wheels to be jacked up as described in Section 2.5, MO I Al and the examination of some rear suspension components require the rear wheels to be Jacked as described in Section 2.6,	That there is enough clearance of the axle or suspension with the bump stop or chassis, and Whether any suspension unit is so weak that it does not hold the body far enough away from the road wheels	Inadequate clearance of the axle or suspension with the bump stop or chassis, or A suspension unit so weak that the body or other part of the vehicle fouls a road wheel or would do so if the vehicle was laden- Note: a missing bump stop rubber is not a reason for rejection.
Checking for wear or play
A small pinch bar should be used to check for wear or play in many of the suspension components covered in this section.	2. Examine the vehicle structure around any sub-frame, spring or suspension component mounting for Excessive corrosion (ie within the ‘prescribed area’, see Appendix C) Distortion Fractures	2. Deliberate modification which significantly reduces the original strength, excessive corrosion, severe distortion, a fracture or an Inadequate repair of a load bearing member or its supporting structure or supporting panelling within 30cm of any sub-frame, spring or a suspension component mounting, that is, within a 'prescribed area', see Appendix C.
Checking for corrosion
Guidance for assessing corrosion and the use of the Corrosion Assessment Tool is given at Appendix C.	Note: It is usually necessary to open the bonnet to inspect front suspension components. It may be necessary to inspect the inside of a luggage compartment or boot to effectively check prescribed areas and testable items that otherwise would not be seen.
Main load bearing structure
The condition of the vehicle main load bearing structure not in a 'prescribed area' is checked under Section 6.
B. Leaf Springs

	1. Examine each leaf spring assembly, check
	a. the condition of spring leaves	a. a cracked or fractured leaf, or one which has been repaired by welding or is permanently distorted due to damage or so deteriorated that it is seriously weakened.
	b. the condition of spring eyes	b. a defective spring eye
	c. the lateral location of spring leaves (particularly leaf splay)	c. the leaves of a multi-leaf spring splayed to such an extent that the action of the spring is impaired, or will foul other parts of the vehicle
	d. leaves for longitudinal displacement	d. a spring leaf longitudinally displaced
	e. the correct location of the springs to the axle for symmetry	e. a spring so fitted that the axle is misaligned
	2. Check the security and the amount of play at the spring anchor bracket pin/bush and both pins/bushes of the spring shackle.	2. Excessive wear in a pin and/or bush, for example more than 2mm for a 12mm diameter pin 3mm for a 25mm diameter pin 10% of the pin diameter for pins over 25mm diameter deterioration of a rubber bush resulting in excessive movement
	3. Check that
	a. anchor/shackle pins are correctly positioned and secure	a. a shackle, anchor or linkage pin not correctly positioned or excessively loose in its bracket
	b. retaining and any locking devices are present and secure	b. a shackle, anchor or linkage pin retaining or locking device, missing or insecurely fitted
	4. Check the side play at spring eyes. Note: For normal leaf suspension, side play at the spring eye should not exceed 6mm.	4. Excessive side play at spring eye.
	5. Check that the spring anchor and shackle brackets are	5. An anchor or shackle bracket
	a. secure and free from signs of movement Note: Attachment of suspension units, eg anchor brackets, may be by bolts, nuts, rivets, welding etc Note: When modified spring anchor or shackle brackets are fitted, there may be more holes in the bracket than holes in the chassis. This is not a reason for rejection.	a. loose to chassis
	b. free from cracks or fractures	b. cracked or fractured
	c. complete with all nuts, bolts and rivets	c. with a nut, bolt or rivet missing
	d. free from excessive damage or corrosion Note: Damage includes damage by weld, eg weld blow holes or cuts which seriously weaken the component	d. damaged or corroded so that it is seriously weakened
	6. Check the security of spring and saddle to the axle
		a. evidence that a spring saddle is fractured or moving relative to the spring
		b. a nut or bolt securing the spring to the axle not secure or missing
C. Coil Springs
Shortened or lowered coil springs Take care when jacking vehicles with shortened or lowered springs fitted. Provided the spring ends locate correctly when the vehicle is lowered into the normal running position, without assistance this is not a reason for rejection.
	1. Examine each spring for general condition. In particular, look for cracks or fractures.	1. A coil spring
		a. incomplete, cracked or fractured
		b. worn or corroded so that its cross sectional area is reduced such that it is seriously weakened
		c. repaired by welding or damaged by excessive heat.
	2. Check that both ends of each spring are correctly located	2. A coil spring not correctly located.
	3. check that the spring mountings are a. secure	3. A coil spring mounting a. loose
	b. free from cracks and fractures	b. cracked or fractured
	c. free from excessive damage or corrosion	c. seriously weakened by damage or corrosion
D. Fluid/Gas/Air Suspension
Care must be taken not to cause damage to body work when pushing down on the suspension.
	1. Check suspension units and accumulators for	1. A suspension unit or accumulator
	a. displacement	a. displaced or totally deflated
	b. damage or serious deterioration	b. damaged or deteriorated so that it is likely to fail
	c. fouling by moving parts	c. fouled by moving parts likely to cause damage or restrict travel
	2. Check for any leak in the system	2. A leak in the system.
	3. Check suspension units’ supply pipes or interconnecting pipes for damage or corrosion.	3. A suspension unit supply pipe or interconnecting pipe damaged or corroded so that it is seriously weakened.
	4. Check the security of a. levelling valves	4. a. an insecure levelling valve
	b. fluid supply pipes and interconnecting pipes	b. an insecure fluid supply pipe or interconnecting pipe
	5. At each corner of the vehicle, where practicable, push down (or pull down from underneath), and note the amount of suspension movement.	5. No suspension movement Note: Large vehicle suspensions can be difficult to move. Ensure there is a defect before rejection.
E. Torsion Bars

	1. Examine the bars for	1. A torsion bar
	a. cracks and fractures	a. cracked or fractured
	b. excessive corrosion and pitting c. Welding or excessive heat	b. deteriorated by corrosion or pitting so that its cross sectional area is reduced and seriously weakened c. Repaired by welding or damaged by excessive heat
	2. Check the end fixings for	2. Insecurity or excessive play at an end fixing.
	a. security
	b. excessive free play
	3. Examine the adjustment assemblies for security.	3. Adjustment assembly inadequately locked.
	4. Check that the attachments of bars are	4. A torsion bar attachment bracket
	a. secure to frame and suspension	a. loose
	b. free from cracks or fractures	b. cracked or fractured
	c. free from excessive damage or corrosion	c. seriously weakened by damage or by corrosion
F. Bonded Suspension Units
This inspection applies to bonded suspension spring units ie rubber cone suspension. Bonded mountings and bushes are to be inspected in accordance with subsection 2.4G.	1. Check that the attachments of units are a. secure	1. A bonded unit attachment a. loose
	b. free from cracks and fractures	b. cracked or fractured
	c. free from excessive damage or corrosion	c. seriously weakened by damage or corrosion
	2. Examine the bonding of the flexible element to its associated metal fixing.	2. Failure of the bonding between flexible element and the metal so that part of unit is likely to become displaced.
	3. Check the general condition of the unit for damage and deterioration of the flexible element.	3. The unit is so damaged or deteriorated that it is no longer capable of carrying out its proper function.
G. Suspension Arms and Linkages, Sub-Frames, etc
Carrying out this inspection The inspections in sub-section 2.4G can be carried out in conjunction with the inspections in . Sub-section 2.5 (Front Suspension, Front Wheel Bearings and Drive Shafts), and . Sub-section 2.6 (Rear Suspension and Rear Wheel Bearings)	1. Check the following members for cracks, fractures, distortion, corrosion, wear and insecurity a. suspension arms (wishbone etc)	1. A member . cracked, fractured or insecure . severely distorted . seriously weakened by corrosion or wear . which is adjustable, and is loose in its adjustment threads, or its locking device insecure or missing . inadequately repaired (See Appendix C) . seriously weakened as a result of deliberate modification
	b. trailing arms
	c. radius arms
	d. tie bars/rods
	e. panhard rods
	f. torque/reaction arms
	g. anti-roll bars and linkages
	h. MacPherson strut casings
	i. sub-frames
	Note: Some vehicles use comparatively thin gauge steel pressings for some highly stressed suspension components. Many of these parts have hollow ‘box sections’ or upfacing areas where road dirt impregnated with salt or other chemicals collects and causes serious but often very local corrosion. Special attention should be paid to these components. See Appendix C for further guidance
	2. Check that an anti-roll bar is fitted to an axle on which it is standard.	2. An anti-roll bar not fitted to an axle on which it is standard
	3. Check the security and the amount of play at pins/bushe/mountings and ball joints locating a. upper and lower suspension arms/wishbones	3. . Excessive play in a pin/bush or pin/ bearing for example more than - 2mm for a 12mm diameter pin - 3mm for a 25mm diameter pin - 10% of the diameter for pins over 25mm diameter . Excessive play in a ball joint . Deterioration of a rubber bush resulting in excessive movement . deterioration of the bonding of a rubber bush/mounting resulting in excessive movement. Note: Some rubber/synthetic bushes are designed to provide a comparatively high degree of compliance. They are therefore likely to show some movement. Such components should normally only be rejected when serious deterioration of the bonding or flexible material is evident.
	b. trailing arms
	c. radius arms
	d. tie-bars/rods
	e. panhard rods
	f. torque/reaction arms
	g. anti-roll bars and linkages
	h. sub-frames
	4. Check that a. linkage pins are correctly positioned and secure	4. A suspension link locating pin a. incorrectly positioned or insecure
	b. retaining and any locking devices are fitted and secure	b. retaining or locking device missing or not properly locked
	5. Check the following suspension attachment brackets for security, cracks, fractures, excessive damage or corrosion and tightness of nuts, bolts etc. a. suspension arms (wishbone etc)	5. A suspension attachment linkage bracket . insecure . cracked or fractured . damaged, corroded or worn to such an extent that its strength is seriously reduced . nut, bolt or rivet missing, or weld cracked . inadequately repaired (See Appendix C) . seriously weakened as a result of deliberate modification
	b. trailing arms
	c. radius arms
	d. tie bars/rods
	e. panhard rods
	f. torque/reaction arms
	g. anti-roll bars h. Sub Frames
	6. On vehicles which have a drive shaft which form part of the suspension, check a. the shaft for distortion, damage and serious corrosion	6. a. a distorted, damaged or excessively corroded drive shaft
	b. the universal joint bearings for excessive play	b. excessive play in a universal joint bearing
	c. the flanges and bolts for security	c. . an incorrectly seated universal joint flange . a loose, missing or inadequately locked flange bolt
Issue Date: 10th January 2005

The Testers Manual

2.4 Suspension - General

Information

Method of Inspection

Reason for rejection

This sub-section applies to

Both front and rear suspensions

A. All Suspension Types

1. Check

How to inspect

That there is enough clearance of the axle or suspension with the bump stop or chassis, and

Whether any suspension unit is so weak that it does not hold the body far enough away from the road wheels

Inadequate clearance of the axle or suspension with the bump stop or chassis, or

A suspension unit so weak that the body or other part of the vehicle fouls a road wheel or would do so if the vehicle was laden- Note: a missing bump stop rubber is not a reason for rejection.

Checking for wear or play

A small pinch bar should be used to check for wear or play in many of the suspension components covered in this section.

2. Examine the vehicle structure around any sub-frame, spring or suspension component mounting for

Excessive corrosion (ie within the ‘prescribed area’, see Appendix C)

Distortion

Fractures

Checking for corrosion

Guidance for assessing corrosion and the use of the Corrosion Assessment Tool is given at Appendix C.

Note: It is usually necessary to open the bonnet to inspect front suspension components. It may be necessary to inspect the inside of a luggage compartment or boot to effectively check prescribed areas and testable items that otherwise would not be seen.

Main load bearing structure

The condition of the vehicle main load bearing structure not in a 'prescribed area' is checked under Section 6.

B. Leaf Springs

1. Examine each leaf spring assembly, check

a. the condition of spring leaves

a. a cracked or fractured leaf, or one which has been repaired by welding or is permanently distorted due to damage or so deteriorated that it is seriously weakened.

b. the condition of spring eyes

b. a defective spring eye

c. the lateral location of spring leaves (particularly leaf splay)

c. the leaves of a multi-leaf spring splayed to such an extent that the action of the spring is impaired, or will foul other parts of the vehicle

d. leaves for longitudinal displacement

d. a spring leaf longitudinally displaced

e. the correct location of the springs to the axle for symmetry

e. a spring so fitted that the axle is misaligned

2. Check the security and the amount of play at the spring anchor bracket pin/bush and both pins/bushes of the spring shackle.

2. Excessive wear in a pin and/or bush, for example more than

2mm for a 12mm diameter pin

3mm for a 25mm diameter pin

10% of the pin diameter for pins over 25mm diameter

deterioration of a rubber bush resulting in excessive movement

3. Check that

a. anchor/shackle pins are correctly positioned and secure

a. a shackle, anchor or linkage pin not correctly positioned or excessively loose in its bracket

b. retaining and any locking devices are present and secure

b. a shackle, anchor or linkage pin retaining or locking device, missing or insecurely fitted

4. Check the side play at spring eyes.

Note: For normal leaf suspension, side play at the spring eye should not exceed 6mm.

4. Excessive side play at spring eye.

5. Check that the spring anchor and shackle brackets are

5. An anchor or shackle bracket

a. secure and free from signs of movement

Note: Attachment of suspension units, eg anchor brackets, may be by bolts, nuts, rivets, welding etc

Note: When modified spring anchor or shackle brackets are fitted, there may be more holes in the bracket than holes in the chassis. This is not a reason for rejection.

a. loose to chassis

b. free from cracks or fractures

b. cracked or fractured

c. complete with all nuts, bolts and rivets

c. with a nut, bolt or rivet missing

d. free from excessive damage or corrosion

Note: Damage includes damage by weld, eg weld blow holes or cuts which seriously weaken the component

d. damaged or corroded so that it is seriously weakened

6. Check the security of spring and saddle to the axle

a. evidence that a spring saddle is fractured or moving relative to the spring

b. a nut or bolt securing the spring to the axle not secure or missing

C. Coil Springs

Shortened or lowered coil springs Take care when jacking vehicles with shortened or lowered springs fitted. Provided the spring ends locate correctly when the vehicle is lowered into the normal running position, without assistance this is not a reason for rejection.

1. Examine each spring for general condition. In particular, look for cracks or fractures.

1. A coil spring

a. incomplete, cracked or fractured

b. worn or corroded so that its cross sectional area is reduced such that it is seriously weakened

c. repaired by welding or damaged by excessive heat.

2. Check that both ends of each spring are correctly located

2. A coil spring not correctly located.

3. check that the spring mountings are

a. secure

3. A coil spring mounting

a. loose

A suspension unit so weak that the body or other part of the vehicle fouls a road wheel or would do so if the vehicle was laden-

Note: a missing bump stop rubber is not a reason for rejection.

Shortened or lowered coil springs

Take care when jacking vehicles with shortened or lowered springs fitted. Provided the spring ends locate correctly when the vehicle is lowered into the normal running position, without assistance this is not a reason for rejection.

b. excessive corrosion and pitting

c. Welding or excessive heat

b. deteriorated by corrosion or pitting so that its cross sectional area is reduced and seriously weakened
c. Repaired by welding or damaged by excessive heat