Mr. J.R. Singal, M.D. - Eastman Industries
Limited receiving National Export Award from the then Honourable
Prime Minister of India -- Mr.Atal Bihari Vajpayee
Care & Safety
Tire Care & Safety
Addo India has always been an advocate of
tire safety. However, there are some situations where a tire failure can't
be avoided, but by taking some simple, time-efficient safety precautions,
drivers can avoid most flat tires. Tire technology has made some remarkable
advancements in the last decade, but to be as safe as possible, drivers
should regularly examine their tires before getting on the road. For more
information on how you can safeguard yourself and your vehicle, please refer
to the Rubber Manufacturers Association
Another way to safeguard yourself and your tires is to register your tires.
Everytime you purchase our tires, request a Department of Transportation
(D.O.T.) card from your dealer. By completing this card, your are ensuring
that we can reach you in the event of a recall.
For the proper mounting of Addo India tires, be sure to observe some basic
Custom or Alloy Wheels
- Wheel is securely seated on the hub face.
- All lugs have proper torque.
- There is no buildup of dirt between the hub and wheel.
- The wheel is not bent.
- Both tire beads are securely seated on the rim.
While custom or alloy wheels require an increased level of care over steel
wheels, it is vitally important that each customer receives the highest
level of service. There are several key points to note when mounting Addo
India tires. Following these basic precautions not only yields consistent
results, but satisfied customersand that translates into return
business and new referrals.
Avoid scratching or bending alloy wheels during installation
These wheels are manufactured with extremely soft metals with a greater
sensitivity to scratching and distortion under pressure. Modern tire
machines apply equal pressure to both top and bottom beads with no pressure
on the wheel itself. A pad on the base of the mounting machine protects
chrome-plated, painted or machined wheels from scratches and damage.
During the mounting process, proper lubrication is a must
Lubricate both top and bottom beads with an approved tire lubricant. If the
beads do not seat at 40 psi, break the entire assembly down and re-lubricate
the bead areas.
Observe match-mounting procedures
Proper tire and wheel assembly balancing is important from a vehicle safety
standpoint. In high-speed driving, improperly balanced tire/wheel assemblies
will cause a vehicle to lose stability and not operate in a safe and
comfortable manner. Improperly balanced tire/wheel assemblies also cause
abnormal treadwear patterns.
To facilitate proper balancing, Addo India places red and yellow marks on
the sidewalls of its tires to enable the best possible match-mounting of the
tire/wheel assembly. There are two methods of match-mounting Addo India
tires to wheel assemblies using these red or yellow marks:
- Uniformity (red mark)
- Weight (yellow mark)
Warning: Improper mounting, underinflation, overloading or tire damage
may result in tire failure, which may lead to serious injury. Tire and rim
sizes must correspond for proper fit and application. Never exceed 40 psi to
seat beads. Warning: Tire changing can be dangerous, and should be done only
by trained persons using proper tools and procedures established by the
Rubber Manufacturers Association. Failure to comply with proper procedures
may result in incorrect positioning of the tire, tube or wheel assembly,
causing the assembly to burst with explosive force sufficient to cause
serious physical injury or death. Never mount or use damaged tires, tubes or
When performing uniformity match-mounting, the red mark on the tire,
indicating the point of maximum radial force variation, should be aligned
with the wheel assembly's point of minimum radial run-out, which is
generally indicated by a colored dot or a notch somewhere on the wheel
assembly (consult manufacturer for details). Radial force variation is the
fluctuation in the force that appears in the rotating axis of a tire when a
specific load is applied and the tire rotated at a specific speed. It is
necessary to minimize radial force variation to ensure trouble-free
installation and operation. Not all wheel assemblies indicate the point of
minimum radial run-out, rendering uniformity match-mounting sometimes
impossible. If the point of minimum radial run-out is not indicated on a
wheel assembly, the weight method of match-mounting should be used instead.
When performing weight match-mounting, the yellow mark on the tire,
indicating the point of lightest weight, should be aligned with the valve
stem on the wheel assembly, which represents the heaviest weight point of
the wheel assembly. After match-mounting by either of the above methods, the
tire/wheel assembly can be balanced.
The technical definition of balance is
the uniform distribution of mass about an axis of rotation, where the center
of gravity is in the same location as the center of rotation. A balanced
tire is one where mass of the tirewhen mounted on its wheel and the
car's axleis uniformly distributed around the axle (its center of
rotation). Balanced tires can spell the difference between a positive and
negative driving experience. Drivers of high performance vehicles will be
more sensitive to imbalance problems, but no driver is happy with an
An out-of-balance tire and wheel assembly:
Sources of Imbalance
- Degrades ride quality and driver comfort.
- Shortens the life of tires, bearings, shock absorbers and other
suspension components. Vibration is the most noticeable effect of
- It is dependent on vehicle speed.
- It often first becomes apparent between 40 and 45 mph and increases
in magnitude with greater speeds.
Two sources of imbalance occur in tires: heavy or light spots in the tire
and radial or lateral run-out. Imbalance also can be caused by:
Heavy or Light Spot Imbalance
- Variations within the wheel, such as thickness and welds.
- Rotor and axle imbalances.
There are two types of imbalance caused by heavy or light spots: static and
Heavy or Light Spot Balancing
- Static imbalance: Occurs when there is a heavy or light spot in the
tire so that the tire won't roll evenly and the tire/wheel assembly
undergoes an up-and-down movement.
- Dynamic imbalance: Occurs when there is unequal weight on both sides
of the tire/wheel assembly's circumferential centerline. The tire/wheel
assembly has a side-to-side movement.
Achieved either statically or dynamically, depending on the type of
imbalance that has occurred.
Radial or Lateral Run-out Imbalance
- Static balance: Achieved with a bubble balancer but does not correct
for dynamic imbalance.
- Dynamic balance: Achieved with a spin balancer where the tire/wheel
assembly is balanced both statically and dynamically.
This results from poor bead seating on the rim or the placement of
components. Poor bead seating is usually the result of improper mounting or
the use of improperly made wheels. A small degree of this imbalance is
acceptable, but too great a run-out causes vibration and excessive tire
- Radial Run-out: An "out-of-round" situation where
vibrations are produced as the wheel spindle moves up and down.
- Lateral Run-out: A side-to-side or wobbling movement of the tire and
wheel. It is less common than radial run-out. Sensitivity of a vehicle
to vibration from radial run-out is four to eight times that of wobble
from lateral run-out.
Depends on whether it is radial or lateral run-out.
- Radial run-out balancing: Achieved by rotating the wheel and tire
assembly two stud positions on the hub, or by rotating the tire 180¡
on the wheel. If run-out is still over specification, check wheel
run-out and mark the low point. Rotate to match the high point of the
assembly run-out with the wheel low point. If the assembly run-out is
still too high and the wheel is within specification, replace the tire.
- Lateral run-out: Achieved by using a run-out gauge to check both the
tire and wheel. Chalk-mark the highest point of run-out on both the
wheel and tire. Replace whichever (wheel, tire, or both) is out of
For improved overall performance and
extended tire tread life under various driving conditions and speeds, it is
imperative that the tires be in proper alignment with the vehicle. Poor or
improper alignment occurs when the suspension and steering systems are out
Several factors may be involved with poor alignment. Be aware that
customers tend to replace tires rather than correct the real problemalignment.
The result can be a dissatisfied customer who switches from one tire
manufacturer to the next with the same result and eventually goes elsewhere
to buy new tires.
For most vehicles, poor alignment results in excessive and/or uneven tire
wear. Improper alignment can reduce a tire's life by more than 70%.
Improper Alignment and Correction
Poor or improper alignment typically results in a variety of abnormal
treadwear patterns that are "readable." These clues often point to
one or more sources of the problem that can be measured and corrected. But
before taking any alignment measurements, check the following:
- Proper inflation of each tire: Pressure over or under recommended
levels will affect some alignment measurements.
- Ride height: Ride height is the distance between the vehicle's frame
and the road. Because all alignment specifications are relationships
between various suspension components, ride height becomes the reference
point for all alignment measurements. Therefore, proper alignment is not
possible if ride height is higher or lower than factory ride height
Refers to the distance between the front and rear axles measured at the hub
centers. This distance should be equal on both sides of the car. If not,
some suspension components are worn, bent or damaged.
Relates to the distance of each wheel to the vehicle's centerline. Each
wheel should be equidistant from this centerline so that, as the vehicle
moves straight ahead, wheel tracks are parallel to the vehicle's centerline
(e.g., the axle should not be cocked).
To determine caster, first draw an imaginary line through the upper and
lower ball joints. The angle made by this line (the steering axis) with
another imaginary line drawn perpendicular to the ground (the centerline) is
the caster. If the angle between the steering axis and centerline is toward
the front of the car, caster is negative. If toward the rear of the car,
caster is positive. Measured in degrees, caster plays a large role in
determining both steering feel and high-speed stability. The goal of proper
caster alignment is to achieve optimal balance between low-speed steering
effort and high-speed stability. An increasingly positive caster enhances
high-speed stability, but increases low-speed steering effort. An
increasingly negative aster decreases low-speed steering effort and
high-speed stability. For cars with power steering, an increase in low-speed
steering effort increases the rate of wear in the power steering system.
With most suspension designs, there is a trade-off between caster and camber
angles at the extreme limits.
Viewed from in front of the vehicle, camber describes tilt of the tire from
vertical. A tire has negative camber when its top inclines toward the
vehicle. Positive camber occurs when its top tilts away from the vehicle.
Camber is measured in degrees, and varies by car model and year. A wheel's
camber angle should be adjusted to maximize a tire's contact with the road's
surface under given loaded cornering conditions. Because a tire's camber
changes slightly as its suspension moves during travel, the static angle at
which the camber is set will depend on driving habits. If a driving style
entails hard cornering, outside tires (heavily loaded) will need to have a
statically set negative camber. If driving is on highways where tires are
mainly subjected to lightly loaded cornering conditions, the static camber
setting should be zero or slightly positive. Camber plays a large role in
determining both the overall handling feel of a vehicle and how a tire wears
across its treadface. A tire wears most at the point(s) where the majority
of the vehicle's load rests. A properly set camber maximizes a tire's
contact patch, leading to even wear. Excessive negative or positive camber
has an adverse effect on treadlife by causing premature outer or inner
If you were able to view the front tires of a vehicle from above the car,
you would expect them to look exactly parallel to each other. In fact, they
rarely are. The difference in distance between the front edge of the tires
and the rear edge is called toe. Toe describes how close to parallel the two
tires are, and whether they are toed-in (closer at the front of the tire) or
toed-out (closer at the rear of the tire). The goal of toe is to provide
proper tire wear through various driving conditions. The amount of toe your
suspension is set to varies by the drive layout of your vehicle, driving
preference, and car's handling characteristics. On a rear-wheel-driven car,
acceleration forces on the tire tend to push the front tires back slightly
in the wheel well. Static toe-in will result in a zero-toe situation at
speed. For a front-wheel-driven vehicle, the front wheels will pull
themselves forward in the wheel wells under acceleration. This happens
because as the (driven) front wheels claw for traction, hey pull themselves
forward, dragging the rest of the car along. For this situation, static
toe-out will result in a zero-toe condition at speed. Assuming that the rest
of the suspension is correctly aligned and maintained, and the tires
properly inflated, toe-in will result in additional understeer for the car.
In a corner the inside front tire will turn at less of an angle than the
outside tire. Additionally, excessive toe-in will result in premature tire
wear through feathering, and increased fuel consumption. Conversely, toe-out
will result in additional oversteer for the vehicle. This occurs as the
inside front tire turns at a greater angle than the outside tire. Thus, in a
corner, the inside tire is trying to turn even more than the heavily-loaded
outside tire. Excessive toe-out will also result in premature tire wear due
to feathering, and increased fuel consumption.