All About Leaf Springs
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![Discover All About Leaf Springs For Your Vehicle Discover All About Leaf Springs For Your Vehicle](/cms/suspension-systems--leaf-springs/images/suspension-systems--leaf-springs-desktop.jpg)
What Is Leaf Springs?
Do you know about a leaf spring? Well, it is a part of the suspension’ system in a number of
vehicles. It is made up of numerous thin strips of metal that are known as
leaves. They are arranged on top of each other to form a single curved piece.
The vehicle’s weight and the bumps are all absorbed by the bending of the
leaves and the friction caused between them when they slightly slide over each
other. Note that these leaf springs are curved and are often referred to as
elliptical springs. The curvature aids the spring absorb the impact.
Where Is Located Leaf Spring?
Generally,
a leaf spring is connected to the body or frame of the vehicle at each and
every end and the wheel or axle assembly is mounted in the middle of the
spring. The spring extends in the same direction along with the vehicle. The
attachment points are there on each side in the front and rear. Various
suspension designs have a single leaf spring connected at each side that is
also known as a traverse spring.
Types of Leaf Springs
Do
you know that light commercial vehicles and HGV’S carry heavier loads? Yes, and
that’s only possible when they have leaf springs fit. So, only for our precious
customers, according to the plates, we have listed here everything you need to
know about the types of leaf springs and their uses:
- Multi
Leaf Springs -
In this type, the spring is composed of multiple metal plates and these plates
are situated on top of each other. Fixed together, these make the operations of
the vehicle a lot easier. As you look
downwards, you will notice the size of plates getting smaller. Generally, the
plates are laid lengthwise for layering. The longest piece located on the top
is made up of eyes and hooks to fix the springs well in place. These are widely
used for light commercial vehicles and heavy good vehicles. Semi elliptical
look is the stacked format that mean that the springs are thicker in the
middle.
- Mono Leaf Springs - These types can mostly be found in the LCV’s than HGV’s as they are not designed for heavier vehicles. There frame includes a thicker centre, that gradually thins out towards the end. It is similar in structure with the multi leaf system but has no added plates. Earlier, the single leaf spring system was used greatly only until the time when they began breaking on heavier vehicles. Nevertheless, you can still find them and use them, although should not be used in a vehicle that needs protection against a heavy load or the weight of the vehicle itself.
Materials Used For Leaf Springs
In
these types, the material that is used is generally a plain carbon steel that
contains 0.90 to 1.0% carbon. Note that the leaves present in it are heat
treated after the forming procedure. The heat treatment of spring steel
products helps acquiring more strength for increased load capacity, range of
deflection and enhanced fatigue properties.
Important Features of Leaf Springs
- Now
that we know that the leaf springs are heavily layered, it should be noted that
these offer a large amount of support between the wheels, axles and the cars'
chassis. Because of their tight knit structure, they can easily bear the heavy
vertical loads that are applied to them. They are mostly used in the heavy-duty
industries. It can be observed that the
vertical loading is also distributed throughout the length of the leaf spring
rather than scarcely through a small spring and damper. This helps in creation of
concentrated force for larger suspension to be handled.
- Damping is a highly essential characteristic in a car. In some cases where the suspension is under-damped, the car will tumble and bounce around well after hitting bumps or potholes that are there on the road. Well, this was a primal property in cars that utilized helical springs before the creation of the shock absorber. It is also disadvantageous to cars when driven at any real pace. Due to friction between each plate of steel, vehicle demoing’s became easily tolerable that made the response time after a vertical flex in the suspension much shorter and controllable for the car.
- These leaf springs have a basic design that involves a cheap production as compared to the early springs and dampers. So, these leaf springs became the go to choose for everyone. Also, the magnolia springs also have a simple design as they use only one leaf spring steel. It is tapered thick in the middle to thin at the edges (referred to as parabolic leaf springs) to distribute the vertical loads evenly. However, this kind of a single leaf framework could only be used on extremely lightweight vehicles because of lack of strength within the bar.
How Do Leaf Springs Work?
- Love
hitting the roads? But wait, is your vehicle bouncing and swaying with heavy
weights? Then you should suspect a problem with the suspension of the vehicle.
Whenever the vehicle’s suspension gets too rigid and the wheels start bouncing
while hitting the roads, there is a problem with the suspension. A good
suspension on the other hand, helps in keeping the wheels on the ground.
Numerous towers make use of leaf springs to attain stability when they have
towed loads to keep the vehicle grounded. Well, leaf springs on larger tow
vehicles are one of the earliest forms of suspension. They aren’t really fancy
when it comes to their installation as they are simply elongated narrow plates
that are connected to the frame of a trailer that rests above or below the
trailer’ axle. These leaf springs come in numerous varieties namely: monoolein
springs or single leaf springs that often consist of one plate of spring steel.
Generally, these are thicker in the middle, while they narrow out towards the
end. These don't offer a lot of strength and suspension for towed vehicles.
Multiload springs should be used by drivers who tow heavier loads as these
contain several leaf springs of different lengths stacked on each other. The
short leaf springs are closer to the bottom. These too have the same elliptical
shape.
- Also,
these leaf springs have varying ends according to their attachment to the
frame. While considering the double-eye leaf springs, you may find the top
plate having the longest ends curved into a circle. These ends form two holes,
that can be bolted to the bottom side of the trailer's frame while on the other
hand, open-eye leaf springs contain only one ‘eye’ or open hole. Generally, the
other end of the open eye leaf spring is a hook end or a flat end.
- Note
that only correct installation of leaf springs ensures best suspension for two
vehicles. The leaf springs can be located behind the wheel (you won’t be able
to see them clearly when they're connected unless you crawl under the trailer).
Take off the wheel completely before starting the installation. Now that the
wheel has been removed, find a pair of hangers located on either side of the
axle. These hangers are small in size and are elongated pieces of metal with
holes that hang down from the frame of the trailer. It is only between the
holes of these hangers where the eyes of a leaf spring are lined. Make sure you
fix them safely with the apt hardware. When the leaf spring is double-eyed, you
are likely to notice one hanger with a shackle link.
- Now
that the leaf springs have been bolted into the hangers, next, you should
install a pair of U-bolts that is a two horseshoe-shaped metal rods. At times,
these leaf springs are over slung (placed over the axle) or underslung (placed
underneath the axle). The U-bolts fit around the axle and are fixed to a metal
plate that rests against the leaf springs. The U-bolts serve the purpose of
keeping the leaf springs flush against the axle so they hold onto the weight of
the cargo.
- Lastly,
we advise you to inspect the leaf springs and their accessories for wear and
tear as a worn or crooked leaf spring can lead to heavy damage (to a trailer
and its contents). Also, while taking leaf springs off, check the shackle links
for damage. A round ring of wear matching to the shape of the nut is absolutely
fine but if the shape becomes an oval, perform a quick replacement of the
shackle link. Properly take care of the leaf springs for safer drives.
Symptoms of Bad Leaf Springs
Here
listed are a number of problems that you are likely to notice when the leaf
springs are bad:
- You
will notice the vehicle leans to one side
- At
times, the vehicle will wander or bottom out
- Constant
spring breakage
- Noisy
springs
Tools Needed for Leaf Springs
There are a number
of skilled auto mechanics who have a goal of opening their own car repair shop
at some point in their career. But let’s face it; if you want to put up an
efficient as well as profit making shop, then you might need much more than
mechanical skills. There are a number of tools which you might need to perform
the car repairs quickly as well as reliably. Auto repair equipment that you
will need to repair your Leaf Springs may include:
Top Brands for Leaf Spring
If customers trust a brand, then it would make them loyal, and if they
are loyal, then they will surely buy more. We are well aware that customers
want comfort, cheerfulness as well as satisfaction in their lives and that’s
the reason why we offer top quality auto parts brands to our customers. We make
sure to provide a positive experience to our consumers from the brands which we
are offering so that they can form an opinion that a particular auto parts
brand is trustworthy and would give them peace of mind while they are
purchasing it for their car. Here we have listed out some top brands for Leaf
Springs:
Related Parts for Leaf Springs
It is very important to arm yourself with information before you shop any auto part. We are here to help you dive deep into the names of the leaf springs related parts:
Total Costs & Repair Times, Effort of Leaf Springs
How to Change Leaf Spring?
Don’t know where to start from? Well, we have mentioned it all for you.
All the information is valid for multiple-leaf springs on rear suspension
systems that have two springs fixed longitudinally in regard to the chassis.
Usually, numerous leaf springs have plastic spring silencers located in between
the spring leaves. When these silencers get damaged, you are likely to hear
screeching noises, while you drive on a rough road at low speeds. First, lift
the vehicle with a floor jack and support the frame on safety stands so that
the rear suspension moves downward, if you want to perform an inspection of the
silencers. For removing the silencer, the vehicle weight shouldn't be applied.
Well, damaged shackle bushings, brackets and mounts lead to excess chassis
lateral movement and rattling noises. When the normal vehicle weight is resting
on the springs, a pry bar should be inserted between the rear outer end of the
spring and the frame and downward pressure should be applied on the bar. Next,
observe the rear shackle for any movement. Remove the shackle bushings,
brackets, or mounts if in case there is any movement in the shackle. Similarly,
follow this process to check the front bushing in the main leaf as a worn out
or damaged spring centre bolt enables the rear axle assembly to move rearward
on one side. This movement can lead to changes in the rear wheel tracking that
results in handling issues, tire deterioration and a fall in directional
stability. Broken rear springs also tend to decrease the curb riding height.
Also, spring replacement is quite essential if the springs are damaged. Still
not there? Follow these instructions:
Step 1 - Lift the vehicle
- All you got to do is park the vehicle in a flat solid surface area as
this helps in giving the vehicle stability by reducing the risk of an accident.
Ensure that the vehicle is not leaning to the side as rolling is a more common
issue because at times an improperly lifted car can tip over.
- Next, utilize a pair of wheel chocks that are wedges that fit under tires to prevent the vehicle from rolling. Note that, wedge 1 of the chocks is located under the front side of the tire. After that, wedge the other chock behind that same tire. Uplift the rear wheels using a floor jack. Crank the jack till the tires are approximately 7.6 cm off the ground. Then put these jack stands in front of the back tires. Place the stands in front of the back wheels (2.5 cm). Make sure that the car’s frame is able to rest on the top side of the stands while keeping the jack stands on the same height. Try pushing the car to see if it is stable before moving on to the removal of the leaf springs. If the vehicle is unstable, lower it onto the jack stands by lowering the floor jack. Check the position of the jack to make sure they are under the vehicle’s frame.
Step 2 - Remove the old springs
- Firstly, wear safety glasses to protect eyes from all the dust. To loosen the parts, sprinkle some spring’s nuts and bolts in oil to prevent any damage while removal. You can use penetrating oil such as WD-40. The leaf springs are elongated, flat, and slightly curved metal strips that extend across the length of the tire. Next, remove the bolts from the shock pads using a ratchet wrench (triangular mounting bracket right next to leaf spring). Generally, it is on the axle and is bolted to a bar that is connected to the car’s underside. The ratchet wrench should be used to turn the bolts counter clockwise for removing the bracket. Register the location of all the parts. Then loosen the U- bolts for removal. These can be found above the shock absorber bracket, hanging off the axle. Twist and turn the nuts counter clockwise to drop the bracket off the bolts. Then slide it. These are horse shaped, so they are easy to locate. Then unscrew the eyelet bolts on the spring’ ends by turning them counter clockwise to slide them off the leaf spring. Then, repeat this to disconnect the bolts on the spring’s back end. Now that you have removed the bolts, make sure that the leaf springs don’t fall. Repeat the steps to remove the other leaf spring that is situated next to the opposite wheel.
Step 3 - Install the new springs
- Place the new leaf spring under the mounting brackets in the way that it looks like a U with the lowest point in the middle. Ensure, to see that it spans across the tire and reaches the mounting brackets at both ends. Then, screw the leaf spring to the front bracket using a ratchet wrench. The leaf spring is mounted in the lowest point of the bracket and hangs down underneath the car. Then slide the eyelet bolt into the bracket and spring by changing the nut and twisting it clockwise. Place the bolt in a way that the car’s head points towards the car’ centre. This will help in preventing the bolt from popping out in case it loosens. Connect the spring to the rear bracket by simply fitting the other end of the spring in the square-shaped bracket at the back end of the wheel. Change the eye bolts and nuts and tighten them until the spring is suspended in the right position. Next, install the U-bolts and shock pad. For that hang the U-bolts over the axle (1 on each side of the spring). Slide the shock pad brackets onto the ends of the bolts. Place the nuts underneath the pads and tighten them to finish securing the parts. Then you need to loosely tighten the nuts for now to ensure that the other parts are placed correctly. Tighten the nuts later, if you do this. Properly put the other leaf spring to the opposite tire. The you should repeat these steps in order to install the replacement spring on the other tire. Place the spring in the brackets and then screw them in place. Ensure that they are screwed tightly so that the spring doesn’t wobble while touching. In case, the pieces seem loose or rattle when the vehicle is driven, readjust the bolts as soon as possible. Finally, remove the floor jacks by using a floor jack to lift the vehicle off of the jack stands. Slide the stands out from under the vehicle, if they are clear. Lower the floor jack to put the car on the ground with its new installed leaf springs.