2021 HYUNDAI SONATA Brake pads

6-20
BrAke SySteM
Power Brakes
Your vehicle has power-assisted brakes
that adjust automatically through normal
usage.
If the engine is not running or is turned
off while driving, the power assist for
the brakes will not work. You can still
stop your vehicle by applying greater
force to the brake pedal than typical.
The stopping distance, however, will be
longer than with power brakes.
When the engine is not running, the
reserve brake power is partially depleted
each time the brake pedal is applied.
Do not pump the brake pedal when the
power assist has been interrupted.
Only pump the brakes on slippery
surfaces if the power assist has been
interrupted to maintain steering control.
Do not pump the brakes on slippery
surfaces if the brakes are operating
normally.
WARNING
Take the following precautions:
• Do not drive with your foot resting
on the brake pedal. This will create
abnormal high brake temperatures,
excessive brake lining and pad wear,
and increased stopping distances.
• When descending down a long or
steep hill, move the gear shift button
to Manual Shift Mode and manually
downshift to a lower gear in order
to control your speed without using
the brake pedal excessively. Applying
the brakes continuously will cause
the brakes to overheat and could
result in a temporary loss of braking
performance.
• Wet brakes may impair the vehicle's
ability to safely slow down; the
vehicle may also pull to one side
when the brakes are applied.
Applying the brakes lightly will
indicate whether they have been
affected in this way. Always test your
brakes in this fashion after driving
through deep water. To dry the
brakes, lightly tap the brake pedal to
heat up the brakes while maintaining
a safe forward speed until brake
performance returns to normal.
Avoid driving at high speeds until the
brakes function correctly.
Disc Brakes Wear Indicator
When your brake pads are worn and new
pads are required, you will hear a high
pitched warning sound from your front
or rear brakes. You may hear this sound
come and go or it may occur whenever
you depress the brake pedal.
Note that some driving conditions or
climates may cause a brake squeal
when you first apply (or lightly apply)
the brakes. This is normal and does not
indicate a problem with your brakes.
NOTICE
To avoid costly brake repairs, do not
continue to drive with worn brake pads.
Information
Always replace brake pads as complete
front or rear axle sets.
While Driving

08
8-9
Normal Maintenanc e Schedule (Smartstream G1.6 T-GDi) (CONT)
MAINTENANCE INTERVALS
MAINTENANCE
ITEM Months 12 24 36 48 60 72 84 96 108 120 132 144 156
Miles×1,000 8 16 24 32 40 48 56 64 72 80 88 96 104 Km×1,000 13 26 39 52 65 78 91 104 117 130 143 156 169
Battery condition I I I I I I I I I I I I I
Brake lines, hoses and connections I I I I I I I I I I I I I
Disc brakes and pads I I I I I I I I I I I I I
Driveshaft and boots I I I I I I I I I I I I I
Suspension mounting bolts I I I I I I I I I I I I I
Air conditioner refrigerant I I I I I I I I I I I I I
Air conditioner compressor I I I I I I I I I I I I I
Exhaust pipe and muffler I I I I I I I I I I I I I
Automatic transmission fluid No check, No service requiredR: Replace or change.
I : Inspect and if necessary, adjust, correct, clean or replace.

08
8-11
Maintenance Under Severe Usage Conditions (Smartstream G1.6 T-GDi)
The following items must be serviced more frequently on cars normally used under
severe driving conditions. Refer to the chart below for the appropriate maintenance
intervals.
R: Replace or change.
I : Inspect and if necessary, adjust, correct, clean or replace.
MAINTENANCE ITEMMAINTENANCE
OPERATION MAINTENANCE
INTERVALS DRIVING
CONDITION
Engine oil and filter *
1R Every 5,000 miles or
6 months A, B, C, D, E, F,
G, H, I, J, K, L
Air cleaner filter RMore frequently C, E
Spark plugs RMore frequently A, B, H, I, K
Automatic transmission fluid R Every 60,000 miles A, C, E, F, G, I
Front brake disc/pads, calipers I More frequently C, D, G, H
Rear brake shoes or disc/pads IMore frequently C, D, G, F
Parking brake IMore frequently C, D, G, H
Steering gear box, linkage &
boots/ lower arm ball joint,
upper arm ball joint I
More frequently C, D, E, F, G,
H, I
Suspension mounting bolts IMore frequently C, D, E, F, G,
H, I
Drive shafts and boots IEvery 3,000 miles or
6 months C, D, E, F, G,
H, I
Climate control air filter
(for evaporator and blower unit) R
More frequently C, E
*1 : Requires grade engine oil. If a lower grade
engine oil (mineral oil including Semi-synthetic) is used, then the engine oil and engine
oil filter must be replaced as indicated for severe maintenance condition.
Severe Driving Conditions
A. Repeatedly driving short distances
of less than 5 miles (8 km) in normal
temperature or less than 10 miles (16
km) in freezing temperature
B.

Ext
ensive engine idling or low speed
driving for long distances
C.
Driving on r

ough, dusty, muddy,
unpaved, graveled or salt- spread
roads
D.
Driving in ar

eas using salt or other
corrosive materials or in very cold
weather
E.

Driving in sandy ar
eas F.
Driving in hea

vy traffic area over 90°F
(32°C)
G. Driving on uphill, do wnhill, or
mountain road
H.

T
owing a Trailer, or using a camper, or
roof rack
I.

Driving as a pa
trol car, taxi, other
commercial use or vehicle towing
J.
Driving o

ver 106 mph (170 km/h)
K. Frequently driving in stop-and-go conditions
L.

E
ngine oil usage which is not
recommended (semi-synthetic, mineral
type, lower grade spec, etc.)

08
8-13
Normal Maintenance Schedule (Smartstream G2.5 GDi) (CONT)
MAINTENANCE INTERVALS
MAINTENANCE
ITEM Months 12 24 36 48 60 72 84 96 108 120 132 144 156
Miles×1,000 8 16 24 32 40 48 56 64 72 80 88 96 104 Km×1,000 13 26 39 52 65 78 91 104 117 130 143 156 169
Battery condition I I I I I I I I I I I I I
Brake lines, hoses and connections I I I I I I I I I I I I I
Disc brakes and pads I I I I I I I I I I I I I
Driveshaft and boots I I I I I I I I I I I I I
Suspension mounting bolts I I I I I I I I I I I I I
Air conditioner refrigerant I I I I I I I I I I I I I
Air conditioner compressor I I I I I I I I I I I I I
Exhaust pipe and muffler I I I I I I I I I I I I I
Automatic transmission fluid No check, No service required
Steering gear rack, linkage and boots IIIR: Replace or change.
I : Inspect and if necessary, adjust, correct, clean or replace.

08
8-15
Maintenance Under Severe Usage Conditions (Smartstream G2.5 GDi)
The following items must be serviced more frequently on cars normally used under
severe driving conditions. Refer to the chart below for the appropriate maintenance
intervals.
R: Replace or change.
I : Inspect and if necessary, adjust, correct, clean or replace.
MAINTENANCE ITEMMAINTENANCE
OPERATION MAINTENANCE
INTERVALS DRIVING
CONDITION
Engine oil and filter *
1R Every 5,000 miles or
6 months A, B, C, D, E, F,
G, H, I, J, K, L
Air cleaner filter RMore frequently C, E
Spark plugs RMore frequently A, B, F, G, H, I, K
Automatic transmission fluid R Every 60,000 miles A, C, E, F, G, I
Front brake disc/pads, calipers I More frequently C, D, G, H
Rear brake shoes or disc/pads I More frequently C, D, G, F
Parking brake IMore frequently C, D, G, H
Steering gear box, linkage &
boots/ lower arm ball joint,
upper arm ball joint I
More frequently C, D, E, F, G,
H, I
Suspension mounting bolts IMore frequently C, D, E, F, G,
H, I
Drive shafts and boots IEvery 3,750 miles or
6 months C, D, E, F, G,
H, I
Climate control air filter
(for evaporator and blower unit) R
More frequently C, E
*1 : Requires grade engine oil. If a lower grade
engine oil (mineral oil including Semi-synthetic) is used, then the engine oil and
engine oil filter must be replaced as indicated for severe maintenance condition.
Severe Driving Conditions
A. Repeatedly driving short distances
of less than 5 miles (8 km) in normal
temperature or less than 10 miles (16
km) in freezing temperature
B.

Ext
ensive engine idling or low speed
driving for long distances
C.
Driving on r

ough, dusty, muddy,
unpaved, graveled or salt- spread
roads
D.
Driving in ar

eas using salt or other
corrosive materials or in very cold
weather
E.

Driving in sandy ar
eas F.
Driving in hea

vy traffic area over 90°F
(32°C)
G. Driving on uphill, do wnhill, or
mountain road
H.

T
owing a Trailer, or using a camper, or
roof rack
I.

Driving as a pa
trol car, taxi, other
commercial use or vehicle towing
J.
Driving o

ver 106 mph (170 km/h)
K. Frequently driving in stop-and-go conditions
L.

E
ngine oil usage which is not
recommended (semi-synthetic, mineral
type, lower grade spec, etc.)

08
8-17
Engine Coolant
The coolant should be changed at the
intervals specified in the maintenance
schedule.
Automatic Transmission Fluid
Automatic transmission fluid should
not be checked under normal usage
conditions. But in severe conditions, the
fluid should be changed at an authorized
HYUNDAI dealer in accordance to the
scheduled maintenance at the beginning
of this chapter.
Information
Automatic transmission fluid color is red
when new.
As the vehicle is driven, the automatic
transmission fluid will begin to look
darker. This is a normal condition and you
should not judge the need to replace the
fluid based upon the changed color.
NOTICE
The use of a non-specified fluid could
result in transmission malfunction
and failure. Use only the specified
automatic transmission fluid (refer
to “Recommended Lubricants and
Capacities” in chapter 2).
Brake Hoses and Lines
Visually check for proper installation,
chafing, cracks, deterioration and any
leakage. Replace any deteriorated or
damaged parts immediately.
Brake Fluid
Check the brake fluid level in the brake
fluid reservoir. The level should be
between the MIN and the MAX marks
on the side of the reservoir. Use only
hydraulic brake fluid conforming to DOT
4 specification.
Parking Brake
Inspect the parking brake system
including the parking brake pedal and
cables.
Brake Discs, Pads, Calipers and
Rotors
Check the pads for excessive wear, discs
for run out and wear, and calipers for
fluid leakage.
Exhaust Pipe and Muffler
Visually inspect the exhaust pipes,
muffler and hangers for cracks,
deterioration, or damage. Start
the engine and listen carefully for
any exhaust gas leakage. Tighten
connections or replace parts as
necessary.

Maintenance
8-36
A cold tire means the vehicle has
been sitting for 3 hours and driven
for less than 1 mile (1.6 km) in that 3
hour period.
Allow the tire to cool before
measuring the inflation pressure.
Always be sure the tire is cold before
inflating to the recommended
pressure.Tire Rotation
To equalize tread wear, HYUNDAI
recommends that the tires
be rotated according to the
maintenance schedule or sooner if
irregular wear develops.
During rotation, check the tires for
correct balance.
When rotating tires, check for
uneven wear and damage. Abnormal
wear is usually caused by incorrect
tire pressure, improper wheel
alignment, out-of-balance wheels,
severe braking or severe cornering.
Look for bumps or bulges in the
tread or side of the tire. Replace
the tire if you find any of these
conditions. Replace the tire if fabric
or cord is visible. After rotation, be
sure to bring the front and rear tire
pressures to specification and check
lug nut tightness (proper torque is
79~94 lbf·ft [11~13 kgf·m]).
„„Without a spare tire
ODH073802
Disc brake pads should be inspected
for wear whenever tires are rotated.