CONSIDERATIONS REQUIRED
WHENwhen RAISING THE 4WD Considerations required raising the 4 W.D . 16/08 When a vehicle’s ride height is raised or lowered, there quite an amount of other things that happen. Such as tail shaft angle change, brake bias can alter, the centre of gravity of the vehicle will change. All of ABSORBER, SUSPENSION, BRAKES, TOWBARS the above will effect the vehicle’s overallSHOCK operation. AND WHEEL ALIGNMENT SPECIALISTS When a vehicle’s ride height is raised or lowered, there are quite a number of things that happen.
50mm or 2 inches is the most common height that 4WD vehicles are lifted. In 2009 the New South Wales
Such as tail shaft angle change, brake bias can alter, the centre of gravity of the vehicle will change. All of the above Government introduced legislation requiring engineering compliance to accompany any lift greater than will effect the vehicle’s overall operation.
50mm. Experience suggests that this is about all that is required to enable a car to tackle difficult terrain
50mm 2 inches is the mostlevel common height that 4WD vehicles are lifted. In 2009 Newthis South Wales requires while or maintaining a good of practicality and serviceability. Any higherthethan generally Government introduced legislation requiring engineering compliance to accompany any lift greater than 50mm. extensive and expensive modifications to related steering and suspension. Experience suggests that this is about all that is required to enable a car to tackle difficult terrain while maintaining lift kits will generate a highAny centre ofthan gravity on the vehicle. a tall and 4WD like a Troop aAfter good market level of practicality and serviceability. higher this generally requiresTake extensive expensive modifications to relatedadd steering and suspension Carrier for instance, a raised suspensioncomponents. kit and then load up the roof rack with a hundred kilograms
supplies and begina to getcentre a very speed travelling along After market liftspares, kits will you generate high of unstable gravity oncar, the when vehicle.cornering Take a tallat4WD likeor a Troop Carrier for laterally sloping roads or tracks. instance, add a raised suspension kit and then load up the roof rack with a hundred kilograms of supplies and spares, you begin to get a very unstable car, when cornering at speed or travelling along laterally sloping roads or tracks.
of
Weare aregoing going have a look at following the following that manifest themselves carout is of taken out of its We to to have a look at the issuesissues that manifest themselves when thewhen car isthe taken its comfort comfort zone: zone: • Centre of Gravity.
• Centre of Gravity • Drive line • Wheel • Alignment. Wheel Alignment • Live• axle angle changes. Live axle angle changes • Centre linethrust verses thrust line • Centre line verses line. • Leaf springs • Leaf springs. • Shock absorbers • Shock absorbers. • Brake Bias (Proportioning valves) • Brake (Proportioning valves). • Bias Flexible Brake hoses • Drive line.
• Flexible Brake hoses.
Centre of Gravity: Centre of Gravity:
• The• C. The of G.is centre of mass of the C.the of calculated G.is the calculated centre of vehicle. The higher the point the more the chance of mass of the vehicle. The higher the point the vehicle “falling over”.
the more the chance of the vehicle
• This is also exaggerated, “falling over”. when owners load up the roof rack with extra fuel and water containers, spare • This is also exaggerated, when owners wheel and luggage. This weight can reach 90 to up the roof rack with extra fuel and 100kgsload .
water containers, spare wheel and
• So, when raising a client’s vehicle, keep it within the luggage. This weight can reach 90 to bounds of safety and sensibility.
•
100kgs . So, when raising a client’s vehicle, keep it within the bounds of safety and sensibility.
Straight advice, specialists you understand and...
ring the angle of the Drive Line:
•
•
•
• • •
•
When raising the 4wd vehicle, the only things that go up are the sprung components, which include the transmission and the transfer case. CONSIDERATIONS REQUIRED 1 Attached to these are the tail shafts, at the end of each tail shaft is a cardan joint (U.J.) These joints really only like working through a maximum angle of around16/08 3° to 5°. If this angle 2 is increased, there is a big chance that a vibration will be created. SHOCK ABSORBER, SUSPENSION, BRAKES, TOWBARS AND WHEEL ALIGNMENT SPECIALISTS Also, what must be taken into consideration, is 3 the matching angles.ofOn singleLine cardan joint, the Altering Wheel Alignment Altering the Angle thea Drive Geometry flange angles are to be phased to be the exact • When raising the 4wd vehicle, the only things that • On coil sprung vehicles with live axles, they are go up are the(as sprung components, which fitted with trailing arm type suspension. The arms are same angle. depicted in image 2) include the
WHEN RAISING THE 4WD
transmission and the transfer case.
mounted to final drive housing and the other end to the chassis rails. 4
• Attached to these are the tail shafts, at the end of each shaft is a can cardan (U.J.). by changing the angle • Therefore when the sprung weight of the vehicle is Also, atail vibration bejoint created raised the rear mounts of the trailing arm also move up These jointsas really like working of the• tail shaft, the only position of thethrough needlearoller bearings have moved on the cross bar. and in turn will rotate the housing forward, effecting: maximum angle of around 3° to 5°. If this angle is If a Cardan joint, Hookes joint, Universal joint has been in service for a number of kilometers, a increased, there is a big chance that a vibration will be • Caster angle. slight brindleing can occur (wear marks) on the cross bar. When the angle alters the needle rollers created. • Pinion flange will move around the shaft and are now in a different position. Thereangle. is a good possibility that this • Also, what must be taken into consideration, is the • Housing moves sideways, because of pan hard bar. may cause a drive line vibration. matching angles. On a single cardan joint, the flange If you are unsure condition ofexact the cardan joint, remove thebox shaft from vehicle • Steering moving offthe centre, whichand will alter angles are toof bethe phased to be the same angle. steering turning circle left to right. (as depicted in image 2). move the joint by hand through it’s full spectrum of articulation to see if there are any “high spots”
or binding. rotational should the be angle smooth• with nothe “free One of waysplay”. to correct this anomaly, is the fitment • Also, aThe vibration can bemovement created by changing of the tail shaft, as the position of the needle roller bearings have moved on the cross bar.
ring Wheel Alignment geometry: • If a Cardan joint, Hookes joint, Universal •
•
joint has been in service for a number of kilometers, a slight can occur (wear marks) on the cross bar. Onbrindleing coils sprung vehicles with live axles, they When the angle alters the needle rollers will move arearound fittedthe with trailing suspension. shaft and arearm now type in a different position. There is aare good possibilitytothat thisdrive may cause a drive The arms mounted final housing line vibration. and the other end to the chassis rails.
of “offset bushes” into the radius arms. This will rotate the housing back to its original position.
• With leaf spring vehicles, the rotation of the pinion angle may not be as bigger problem, but the same tail shaft issues could exist.
• If you are unsure of the condition of the of cardan Therefore when the sprung weight the joint, remove the shaft from the vehicle and move the joint vehicle is raised the rear mounts of the trailing by hand through it’s full spectrum of articulation to see arm alsoare move up and in turn will rotate the if there any “high spots” or binding. The rotational housing forward, effecting: movement should be smooth with no “free play”. • Caster angle nly things s, which • Pinion flange angle sfer case. • Housing moves sideways, because of pan hard 1 at the end of bar • through aSteering box moving off centre, which will alter steering turning circle2 left to right. f this angle t a vibration • One of the ways to correct this anomaly, is the fitment of “offset bushes” into the radius arms. eration, is This will rotate the housing back to its original 3 dan joint, the the exact position. • With leaf spring vehicles, the rotation of the pinion angle may not be as bigger problem, but 4 the same tail shaft issues could exist.
ing the angle dle roller bearings have moved on the cross bar. joint has been in service for a number of kilometers, a on the cross bar. When the angle alters the needle rollers n a different position. There is a good possibility that this
Straight advice, specialists you understand and...
The correct position of the swinging shackle:
The angle of the swinging shackle is very important. As you are aware, they are fitted to allow for the varying length of the spring when compressing and rebounding. correct positionthe of the swinging • If the original springs are reset The to raise the vehicle, situation willshackle: probably arise that, CONSIDERATIONS REQUIRED because extra camber has been set into the spring, the distance between the eyes is shorter. • Now what happens when fitted to a vehicle, is that the shackles will face inwards, when the angle of the shackle very important. As you are aware, they are fitted spring is worked hard, there is aThe possibility thatswinging the shackle willisinvert. varying length of the spring when compressing and rebounding. • Use a longer main leaf, or new Pedders leaf springs. 16/08 • If the original springs are reset to raise the vehicle, the situation will prob
WHEN RAISING THE 4WD The correct position of the swinging shackle:
because extra camber has been set into the spring, the distance between t
SHOCK BRAKES, TOWBARS • ABSORBER, Now whatSUSPENSION, happens when fitted to a vehicle, is that the shackles will face AND WHEEL ALIGNMENT SPECIALISTS The angle of the swinging shackle is very important. As you are aware, they are fitted to allow for
spring is worked hard, there is a possibility that the shackle will invert.
varying length of the spring and rebounding. • Use a longer mainwhen leaf,compressing or new Pedders leaf springs. The Correct Position of the Swinging Shackle • If the original springs are reset to raise the vehicle, the situation will probably arise th The angle of the swinging shackle is very important. As because extra camber has been set into the spring, the distance between the eyes is sh • Now what happens when fitted to a vehicle, is that the shackles will face inwards, wh you are aware, they are fitted to allow for the varying spring is worked hard, there is a possibility that the shackle will invert. length of the spring when compressing and rebounding. • Use a longer main leaf, or new Pedders leaf springs.
• If the original springs are reset to raise the vehicle, the situation will probably arise that, because extra camber has been set into the spring, the distance between the eyes is shorter.
The use of Dampers (Shock Absorbers):
• Now what happens when fitted to a vehicle, is that the shackles will face inwards, when the spring is worked • hard, The there use of length at ALL times is is correct a possibility thatdampers the shackle will invert.
important • Measure from top to bottom mount atuse fullofdroop (Max. open)Absorbers): Theleaf Dampers (Shock • Use a longer main leaf, or new Pedders springs. • Then with the vehicle at loaded ride height, The use of Dampers (Shock Absorbers): The Use ofbetween Dampers Absorbers) measure the(Shock bump stop and the strike • The use of correct length dampers at ALL times is important plate do notlength forgetdampers to allowatfor • The use of correct length dampers at ALL times is important • The useand of correct ALLcompression times • isMeasure from top to bottom mount at full droop (Max. open) • Measure from top to bottom mount at full droop (Max. open) of the bump stop. (see Fig. 3) important. • Then withwith the the vehicle ride height, • Then vehicleatat loaded loaded ride height, •• MThis will give you the operating window of measure the measure between thebump bump stop thethe strike between the stopand and strike easure from top to bottom mount at full droop (Max. plate do and not do not forgetto to allow allow for compression damper plate and forget for compression open). the bump stop. (see Fig. 3) • But, there is a catch, if the vehicle has been of raised theofbump stop. (see Fig. 3) • Then with the vehicle at loaded ride height, measure• This will give you the operating window of the 50mm, then the shock will need to have an extra • This will give you the operating window of the damper between the bump stop and the strike plate and do • But, there is a catch, if the vehicle has been raised 50mm But what happens to that extra damper not forgetoftorebound. allow for compression of the bump stop. 50mm,isthen the shock will vehicle need to have extra raised • But, there a catch, if the hasanbeen 25mm when the vehicle experiences a huge (see Fig. 3). 50mm of rebound. But what happens to that extra 50mm, then the shock will need to have an extra impact and uses all the bump stroke. There is a • This will give you the operating window of the damper. 25mm when the vehicle experiences a huge 50mm of But to isthat and uses all thewhat bump happens stroke. There a extra big possibility that the unit will bottom out and impactrebound. big possibility that the unit will bottom out and • Bcause ut, there is a catch, if the vehicle has been raised25mm when the vehicle experiences a huge = damage to the shock absorber internals . cause damage to the absorber internals . is a 50mm, then the shock will need to have an extra impact uses all theshock bump stroke. There • The answer: fit 25mm longer bump stops. • Theand = answer: fit 25mm longer bump stops. 50mm of rebound. But what happens to that extrabig possibility that the unit will bottom out and • Always take into account the motion ratio of the • 25mm Always take into account the motion ratio of the when the vehicle experiences a huge impact causedamper damage to calculating the shockoperational absorberlength. internals . when damper when calculating and uses all the bump stroke. operational There is a biglength. possibility •
The answer: fit 25mm longer bump stops.
that the unit will bottom out and cause damage to the • Always take into account the motion ratio of the shock absorber internals .
damper when calculating operational length.
• The answer: fit 25mm longer bump stops. • Always take into account the motion ratio of the damper when calculating operational length.
I.L. = Installed length of the shock absorber, B.S.C. = Bump stop clearance, B.S.H. = Bump stop h đ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľ 95 ) = ( 435 − 100 − ) = ( 335 – 63 ) =272mm Compressed Length = ( đ??źđ??źđ??źđ??źđ??źđ??źđ??źđ??ź − đ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľ − 1.5 1.5
I.L. = Installed length of the shock absorber, B.S.C. = Bump stop clearance, B.S.H. = Bump stop height Compressed Length = ( IL – BC – (
BHS
) ) = ( 435 – 100 –
95
) = ( 335 – 63 ) =272mm of C.L.
1.5 I.L. = Installed length of the shock absorber, 1.5 B.S.C. = Bump stop clearance, B.S.H. = Bump stop height đ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľ 95 Compressed Length = ( đ??źđ??źđ??źđ??źđ??źđ??źđ??źđ??ź − đ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľ − ) = ( 435 − 100 − ) = ( 335 – 63 ) =272mm of C.L. I.L. = Installed length of the shock absorber, B.S.C. = Bump stop clearance, B.S.H. =
1.5
1.5
Compressed Length = ( đ??źđ??źđ??źđ??źđ??źđ??źđ??źđ??ź − đ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľ −
đ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľđ??ľ 1.5
) = ( 435 − 100 −
Straight advice, specialists you understand and...
95
1.5
) = ( 335 – 63
CONSIDERATIONS REQUIRED
WHEN RAISING THE 4WD 16/08 SHOCK ABSORBER, SUSPENSION, BRAKES, TOWBARS AND WHEEL ALIGNMENT SPECIALISTS
Brakes: Bias Adjusters • Most large 4W.D. or ute type vehicle may be equipped with load sensitive Brake Proportioning Valves. • The way they operate is that, when a load is applied over the rear axle and the chassis goes down, pressure is altered on the valve and this will increase rear braking effect.
• W the loadwith is removed, the rear goesProportioning up changing vehicle may behen equipped load sensitive Brake the pressure on the valve and therefore decreasing brake hydraulic pressure.
when a load is applied over the rear axle and the chassis goes • W henwill raising a 4W.D. are indirectly he valve and this increase rearwe braking effect. telling the bias valve that there is no weight on rear and therefore e rear goes up changing the pressure on the the valve and therefore there is no need for full brake pressure to be applied essure. to the rear. It is prudent to check the brake pressure to indirectly telling the bias valve that there is no weight on the rear see if an adjustment is required. for full brake pressure to be applied to the rear. It is prudent to e if an adjustment is required. • To validate the adjustment. You can always check the ou can always check the pressure gauge andto hose pressure with a gaugewith andahose fitted the fitted bleedto heel cylinder.nipple port at the wheel cylinder. rs store and have thealso car checked the Beissbarth Test Lane, • Y ou can visit youron Pedders store and have the car before and after brake pressure check. checked on the Beissbarth Test Lane, brake rollers, by g vehicles can have thisaproblem. conducting before and after brake pressure check. • Note: both coil and leaf sprung vehicles can have this problem.
hoses
Flexible Brake Hoses
• I would recommend that this procedure take place on any vehicle that has been taken out of its standard operating range.
Braking Efficiency The final consideration is brakes, how efficient will they be, with a car that has an increased Gross Vehicle Mass. (GVM) and the Gross Combination Vehicle Mass (GCVM) when towing. All of the following will affect the braking efficiency: Dual fuel tanks, Dual Fuel(gas), shelving and/or racks in the back, de-bogging equipment, camping gear, supplies, roof rack, extra spare wheel,20l of water and finally larger wheels and tyres. The brakes were designed on that vehicle to perform at a given weight, now that there has been more weight added and larger wheels and tyres fitted, the brakes may not perform as efficiently as they might on a standard vehicle. The customer has gone to great lengths to raise the vehicle, fitted H.D. suspension to carry the loads but done zero about improving the stopping power of the vehicle. So, when you are discussing a TrakRyder Lift Kit, a TrakRyder Suspension Kit or Towing Aides with your customer, please talk to him about the possible requirements for upgrading the braking system so it will capable of handling the extra mass.
ength ill ea es. oth d it e
edure been range.
• There is a requirement to check both front and rear on full extension and it does not make any difference if the vehicle is coil or leaf sprung.
4X4/SUV BRAKE PADS
CERAMIC TECHNOLOGY
• The checking of the flexible brake hoses is very important. If there is more extension travel than the flexible length of the brake hose, then the hose will separate from the union and create a fluid leak and in turn no rear brakes.
cient will they be, with Mass. (GVM) and the M) when towing. All of ency: and/or racks in the back, plies, roof rack, extra spare wheel,20l of water and finally larger
SLOTTED 4WD/SUV ROTOR GEOMET COATED
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