1993 DODGE TRUCK service schedule

•
• —
LUiRICATlON
AND
MAINTENANCE
0 - 1
CONTENTS

page
page

CHASSIS
AND
BODY
28
ENGINE MAINTENANCE
14
DRIVETRAIN
.,,, 22
GENERAL INFORMATION
1

GENERAL
INFORMATION INDEl

page

Classification
of
Lubricants
. 3

Components
Requiring
No
Lubrication
4

Fuel Requirements
. 2
Introduction
1

Lubrication
and
Replacement Parts Recommendation
3
page

Routine Maintenance
2

Starting
Assistance (Jump Starting)
9

Vehicle
Lifting
Recommendations
............ 10

Vehicle Noise
Control
2

Vehicle Towing Recommendations
11

INTRODUCTION
Lubrication and maintenance is divided into re­
quired and recommended service tasks. The required service tasks must be completed to verify the emis­
sion controls function correctly. The recommended
service tasks should be completed to maintain safety
and durability. This information will assist the service personnel
in providing maximum protection for each owner's
vehicle. Conditions can vary with individual driving habits.
It is necessary to schedule maintenance as a time in­
terval as well as a distance interval. It is the owner's responsibility to determine the ap­
plicable driving condition. Also to have the vehicle serviced according to the maintenance schedule, and
to pay for the necessary parts and labor. Vehicles with a Gross Vehicle Weight Rating
(GVWR) of 3 855 kg (8,500 lbs.) or less must conform
to light duty emission standards. Vehicles with a Gross Vehicle Weight Rating (GVWR) of 3 856 kg
(8,501 lbs.) or more must conform to heavy duty
emission standards. The GVWR for each vehicle is listed on the Safety
Certification Label. This label is affixed to the driver
side door pillar (Fig. 1).
Additional maintenance and lubrication informa­
tion is listed in the Owner's Manual.
Mm
rv
CHRYSLER
DATE
OF MFR
MFD BY CORPORATION
GVWR
GAWR FRONT
GAWR REAR
WITH
TIRES

WITH
TIRES
RIMS
AT

RIMS
AT

PSI
COLD

PSI
COLD THIS VEHICLE CONFORMS
TO
ALL APPLICABLE FEDERAL MOTOR VEHICLE SAFETY

STANDARDS
IN
EFFECT ON
THE
DATE
OF
MANUFACTURE SHOWN ABOVE.

SINGLE
DUAL

BAR
CODE

VEHICLE MADE
IN

4648503
J9UN-25

Fig. 1 Vehicle Safety
Certification
Label

SEVERE DRIVING
CONDITIONS
Vehicles subjected to severe driving conditions
should decrease the interval between component
maintenance. Severe driving conditions are defined
as:

• Frequent short trip driving less than 24 km (15
miles)
• Frequent driving in dusty conditions
• Trailer towing
• Extensive engine idling
• Sustained high speed operation
• Desert operation
• Frequent starting and stopping
• Cold climate operation

LUBRICATION
AND
MAINTENANCE

0 - 2
LUBRICATION
AND
MAINTENANCE

• Commercial service
When a vehicle is continuously subjected to severe
driving conditions, lubricate:
• Body components
• All the driveline coupling joints
• Steering linkage More often than normal driving conditions

DUSTY
AREAS
With this type of severe driving condition, special
care should be given to the:
• Engine air cleaner filter
• PCV filter
• Crankcase ventilation system
• Brake booster control valve air filter. Verify that the filters and the associated compo­
nents are clean. Also verify that they are functioning
effectively. This will minimize the amount of abra­ sive particles that enter the engine.

OFF-ROAD
(4WD)
OPERATION
After off-road (4WD) operation, inspect the under­
side of the vehicle. Inspect the:
• Tires
• Body structure
• Steering components
• Suspension components • Exhaust system
• Threaded fasteners

HARSH
SURFACE ENVIRONMENTS
After extended operation in harsh environments,
the brake drums, brake linings, and rear wheel bear­ ings should be inspected and cleaned. This will pre­
vent wear and erratic brake action.

ROUTINE MAINTENANCE
The following routine maintenance is recommended
on a monthly basis: TIRES—Inspect the tires for unusual wear/damage.
Determine if the inflation pressure is adequate for
the vehicle load. BATTERY—Inspect and clean the terminals.
Tighten the terminals if necessary. FLUIDS—Determine if the component fluid levels
are acceptable. Add fluid, if necessary. LIGHTS/ELECTRICAL—Test all the electrical sys­
tems in the vehicle for proper operation. It is also recommended that the engine oil and the
washer fluid level be determined at each fuel fill-up.

VEHICLE
NOISE CONTROL
Vehicles with a GVWR of 4 535 kg (10,000 lbs), or
more, are required to comply with Federal Exterior Noise Regulations (Fig. 2).
VEHICLE
NOISE
EMISSION
CONTROL INFORMATION

DATE
OF
VEHICLE
MANUFACTURE

THIS
VEHICLE CONFORMS
TO
U.S. EPA REGULATIONS FOR NOISE EMISSION

APPLICABLE
TO
MEDIUM
AND HEAVY
DUTY
TRUCKS. THE
FOLLOWING
ACTS OR THE CAUSING THEREOF BY ANY PERSON ARE PROHIBITED BY THE NOISE CONTROL ACT
OF 1972. (A) THE
REMOVAL
OR

RENDERING
INOPERATIVE, OTHER
THAN
FOR
PURPOSES
OF
MAINTENANCE,
REPAIR.
OR REPLACEMENT, OF ANY NOISE CONTROL DEVICE OR ELEMENT OF
DESIGN
(LISTED
IN
THE
OWNERS
MANUAL)
INCORPORATED
INTO
THIS
VEHICLE
IN COMPLIANCE
WITH
THE NOISE CONTROL
ACT:
(B) THE
USE
OF
THIS
VEHICLE
AFTER SUCH DEVICE
OR
ELEMENT
OF
DESIGN HAS BEEN REMOVED
OR
RENDERED
INOPERATIVE.

PU626D

Fig.
2 Vehicle
Noise
Emission
Control Information
Label

UNAUTHORIZED
DEFEAT
OF
NOISE
CONTROL COMPONENTS
Federal law prohibits removal, altering or other­
wise defeating any noise control component. This in­
cludes before or after the vehicle is in use. Federal
law also prohibits the use of a vehicle after a noise
control component is defeated.

REQUIRED MAINTENANCE/SERVICE
FOR
NOISE
CONTROL

The following maintenance is required after each
6-month or 9 600 km (6,000 miles) interval. This will
ensure that the vehicle noise control components are
operating properly.

EXHAUST SYSTEM
Inspect exhaust system for exhaust leaks and dam­
aged components. The exhaust hangers, clamps and
U-bolts should be attached and in good condition.
Burned or ruptured mufflers, damaged exhaust pipes should be replaced. Refer to Group 11—Exhaust Sys­
tem/Intake Manifold for service information.

AIR
FILTER
HOUSING/CANISTER
Inspect the air filter assembly for proper fit. Verify
the cover is securely attached to the housing/canis­
ter. Inspect all the air filter housing hoses for con­ nections. The gasket between the air filter housing and throttle body must be in good condition. The air
filter element should be clean and serviced according
to the maintenance schedule.

FUEL
REQUIREMENTS
GASOLINE
ENGINES
All engines require the use of unleaded gasoline to
reduce the effects of lead to the environment. Also unleaded fuel is necessary to prevent damage to the
catalytic converter/02 sensor. The fuel must have a
minimum octane rating of 87 based on the (R + M)/2
calculation method.

GASOLINE ENGINE MAINTENANCE SCHEDULE

LIGHT
DUTY
CYCLE

SCHEDULED
MAINTENANCE
FOR
EMISSIONS
CONTROL
-
PROPER
VEHICLE
PERFORMANCE

Inspection and service is also necessary any
rime
a
malfunction
is observed or suspected.

X
= Scheduled maintenance for all vehicles.

O
= Scheduled maintenance for all vehicles, Recommended for proper
vehicle
performance.
Where both
time
and mileage Miles (Thousand) are
shown,
follow the
interval

which
occurs
first. Kilometers (Thousand) 7'A
15
22'A
30
37'A
45
52'A

60
67'A
75
82'A

90 97'/2 105 112'A
120
Where both
time
and mileage Miles (Thousand)
are
shown,
follow the
interval

which
occurs
first. Kilometers (Thousand) 12 24
36 48
60 72 84 96 108 120
132 144 156 168 180 192

Coolant
Condition,
Coolant
Hoses/Clomps
X X X X X X

O O O O O
O O O
o
O

Exhaust
System—Check
X
X X X X

X
O O O

o
O
O O
o o o

Oil—Change
(6 months)
X X X X X X

O O O

o o

O O
o o
o
Oil Filter—Change (2nd Oil Change)
X
X X
o o
O
o
o

Spark
Plug—Replace
X

0
o o

Air
Filter—Replace
X

o

O
o

Coolant—Flush/Replace
(36 months) &
24
months/48 000 km
(30,000
miles)
thereafter
O

X
X

PCV
Valve—Replace if
Necessary
O'
O' O'

Battery—Replace
O

This maintenance is recommended by Chrysler Corporation to the owner, but is not
required
to
maintain
the
warranty.

0 - 6
LUBRICATION
AND
MAINTENANCE
GASOLINE ENGINE MAINTENANCE SCHEDULE

HEAVY
DUTY
CYCLE

Inspection and service is also necessary anytime
a
malfunction is observed or suspected.
When both
time
and mileage
are
Miles (Thousand)

shewn,
follow
the
interval

which occurs first. Kilometers (Thousand) 6
12 18 24
30 36 42 48 54
60 66 72

78
82V2
84 90
96
102 108
When both
time
and mileage
are
Miles (Thousand)

shewn,
follow
the
interval

which occurs first. Kilometers (Thousand) 9.6 19 29
38 48 58 67 77
85 96 106 116
125 132
135
145
154 164
174

Coolant
Condition, Coolant
Hoses/Clamps
X
X X X
X X X X
X X X X
X X X
X X X

Exhaust
System
—
Check
X X X X X X X X X X X
X X X X X
X X

Oil
—
Change
(6
Months)
X X X X X X X
X X

X
X
X

X X X

X X
X

Oil
Filter
—
Change (2nd
Oil
Change)
X X X X
X X
X X
X

Drive Belt Tension
—
Inspect
&
Adjust
X' X
X1

X X' X

Drive Belts (V-Type)
—
Replace
X

Air
Filter/Air
Pump
Air
Filter
—
Replace
X X X
X

Crankcase
Inlet
Air
Filter
(6 &
8
Cyl.
Eng.
Only)
—
Clean
X X
X X

Spark
Plug
—
Replace
X X X

Fuel
Filter
—
Replace as necessary

Coolant
—
Flush/Replace
(36
months)
& 24
months/48
000 km

(30,000
miles)
thereafter
X
EGR
Valve
&
Tube
—
Replace X2

EGR
Tube
—
Clean Passengers
X2
PCV
Valve
—
Replace X2

Vacuum
Emission
Components
—
Replace
X

Ignition Timing
—
Adjust
to
Specs,
as necessary X
Ignition Cables, Distributor Cap
&
Rotor
—
Replace
X

Manifold Heat Control Valve
—
Lubricate
X

Battery
—
Replace X

Oxygen
Sensor
—
Replace
X2

1 For California vehicles, this maintenance is recommended
by
Chrysler Motors
to the
owner but, is not
required
to
maintain the
warranty
on the
air
pump drive
belt.

2 Requires
Emission
Maintenance Reminder Light.
If
so equipped, these parts
are to be
replaced
at the
indicated mileage,
or
when the
emissions
maintenance reminded light remains on continuously
with
the key in the
"on" position, whichever occurs first.
J9100-20

DIESEL
ENGINE
MAINTENANCE
SCHEDULE
HEAVY
DUTY
CYCLE
Inspection
and
service
is
also
necessary
any
time
a
malfunction
is
observed
or
suspected.

Iff both
time
and distance Miles (Thousand)
are listed, use the
interval

that
ends
first. Kilometers (Thousand) 6
12
18 24
30 36 42

4S
54
60 66
72 78
84 90 96
102 108
Iff both
time
and distance Miles (Thousand)
are listed, use the
interval

that
ends
first. Kilometers (Thousand) 9,6 19
29
38 48 58 67

77

85 96 106
116 125 135 145 154
164 174

Coolant
Condition, Coolant
Hoses/Clamps
(12 months)

Coolant
Flush/Replace (36 months) & 24 months/
48 000 km
(30,000
miles)
thereafter
O

Oil—Change
(6 months)
X X X
X X X
X X X X X
X X X X X X
X

Oil Filter—Replace (Every Oil Change)
X X X
X X X
X X
X X X
X
X X X X
X X

Drive Belts—Replace
As
Necessary
X X
X X X X

Air Filter—Replace
X X
X X

Air Filter—Clean (California Only) e

®

• •
Air
Filter
Canister—Clean
o o o
o

Fuel Filter—Service When Necessary

Injection
Pump
Timing & Engine Idle Speed—

Check
& Adjust
©

• 9 • • •
Underhood Rubber/Plastic Components—Inspect/Replace • • • • •

X
— All vehicles
O
— All
vehicles
except
California.
Recommended
for
California.
•
— California only.
Recommended
for all vehicles.

•

LUBRICATION
AND
MAINTENANCE
0 - 15
DIESEL
ENGINES

The Diesel engine oil level indicator is located at
the left center of the engine, above the
fuel
injection

pump (Fig. 3).

Fig.
3
Diesel
Engine
Oil
Dipstick

ACCEPTABLE
OIL
LEVEL
To maintain proper lubrication of an engine, the
engine oil must be maintained at an acceptable level.
For gasoline engines, the acceptable levels are indi­ cated between the ADD and
FULL
marks on oil
dip­
stick. For Diesel engines, the acceptable levels are
indicated between the L (low) and H
(high) marks
on
oil dipstick. The oil level should be checked periodically. The
vehicle should be on a level surface. Wait for
five
minutes after stopping the engine. For gasoline en­
gines,
add oil only when the level indicated on the
dipstick is at or below the ADD mark. For Diesel en­
gines,
add oil only when the level indicated on the
dipstick is between the L and H marks.
Never oper­
ate a Diesel
engine when
the oil
level
is below
the L mark. The distance between the L and H
marks represents 1.9L (2 Qts) engine oil.

CAUTION:
Do not
overfill
an
engine crankcase
with

oil. This
will
cause
oil
aeration
and
result
in a de­

crease
in the
engine
oil
pressure.
ENGINE
OIL
CHANGE AND FILTER REPLACEMENT

WARNING: PROTECTIVE CLOTHING
AND
GLOVES SHOULD
BE
WORN. EXPOSED SKIN SHOULD
BE

WASHED
WITH
SOAP
AND
WATER
TO
REMOVE
USED
ENGINE
OIL.
DO NOT
USE
GASOLINE, THIN­
NER,
OR
SOLVENTS
TO
REMOVE ENGINE
OIL

FROM
SKIN.
DO NOT
POLLUTE. DISPOSE
OF
USED
ENGINE
OIL
PROPERLY.
ENGINE
OIL
FILTER

All engines are equipped with a throw-away type
oil filter. The same type of filter is recommended
when the filter is changed.

OIL CHANGE
AND
FILTER
REPLACEMENT
Bring engine up to normal operating temperature.
A more complete drainage of oil will result.
(1) Remove the drain hole plug and drain the en­
gine oil from the crankcase.
(2) Install the drain hole plug with a replacement
gasket. For gasoline engines, the oil filter should be
replaced during every second engine oil change.
For Diesel engines, the oil filter should be re­
placed during every engine oil change.
(3) Rotate the oil filter counterclockwise to remove
it.
(4) Clean the engine cylinder block oil filter boss. (5) Apply a light coat of new engine oil to the rub­
ber seal on the oil filter.
(6) Install and hand tighten the oil filter 1/2 to 3/4
of a turn clockwise. (7) Add new engine oil at the fill hole location on
top of the engine cylinder head cover. Wipe off any spilled oil.
(8) Observe the oil level on the dipstick.

CAUTION:
Do not
overfill
the
engine crankcase
with

oil.
(9)
Start the engine. Observe the oil pressure
gauge or warning lamp (as applicable). If the oil
pressure does not increase, stop the engine immedi­ ately. Check oil level.

COOLING SYSTEM

WARNING:
USE
EXTREME CAUTION WHEN
THE
ENGINE
IS
OPERATING.
DO NOT PUT
YOUR
HANDS NEAR
THE
DRIVE BELT(S), PULLEYS
OR
FAN BLADE.
DO NOT
STAND
IN A
DIRECT LINE
WITH
THE FAN
BLADE.

INSPECTION SCHEDULE
Determine the coolant level. Inspect the cooling
system hoses/clamps after each service interval has
elapsed.

COOLANT LEVEL
It is recommended that the engine coolant level be
inspected at least once a month during periods of hot
weather.
With the engine at normal operating temperature,
check the coolant level in the coolant reserve tank.
The coolant level must be at least above the ADD mark. Add coolant to the coolant reserve tank only.

0-18
LUBRICATION
AND
MAINTENANCE

•
COOLANT FREEZE PROTECTION

Cooling systems contain a 50/50 mixture of anti­
freeze (ethylene glycol) and distilled water. This is
the recommended coolant mixture.
It is recommended that the degree of coolant pro­
tection be tested every 12 months. If the coolant is
contaminated or rusty, the cooling system should be
drained, flushed. Refill with a 50/50 mixture of fresh
coolant. Refer to Group 7—Cooling Systems for addi­
tional information.

SYSTEM
INSPECTION

WARNING:
IF THE
ENGINE
HAS
BEEN RECENTLY
OPERATED,
DO NOT
REMOVE
THE
RADIATOR

CAP.
THIS WILL AVOID
YOU
BEING SCALDED

WITH
HOT, PRESSURIZED COOLANT.

(1) Test the radiator cap for proper sealing and op­
eration. Use caution when removing the radiator cap
to avoid contact with hot coolant. Place a heavy rag
or towel over the cap and turn to the first stop. Do
not press down. Pause to allow the pressure to re­
lease through the overflow tube. Then press down
and turn counterclockwise to remove the cap.
(2) Inspect the coolant overflow tubing and the
connections at the coolant reserve tank and at the
radiator.
(3) Inspect the entire cooling system for leaks. A
black-light detector can be used as an aid in detect­ ing the source of coolant leaks.
(4) Inspect the radiator and air conditioner con­
denser fins for debris, etc. (5) If necessary, refer to Group 7—Cooling Systems
for additional information and service procedures.

RADIATOR CAP
The radiator cap must be completely tightened to
provide proper pressure. Inspect and test radiator cap
when cooling system service is performed.

MAIN,
FLUSH
AND
FILL

WARNING: ANTI-FREEZE (ETHYLENE GLYCOL)
IS
POISONOUS.
KEEP
OUT OF THE
REACH
OF
CHIL­

DREN.

Drain, flush, and fill the cooling system at the in­
terval specified in maintenance schedule. For proper service instructions see Group 7, Cooling System.

HOSES AND
FITTINGS
It is recommended that rubber hoses be periodi­
cally inspected. Inspect all hose fittings for looseness and corrosion.
ENGINE
AIR
CLEANER
FILTER
ELEMENT

MAINTENANCE
SCHEDULE
With normal driving conditions, the engine air
cleaner filter element should be replaced:
• Light-Duty Cycle-after each 48 000 km (30,000
miles) interval has elapsed
• Heavy-Duty Cycle-after
each
38 000 km (24,000
miles) interval has elapsed
When the vehicle is operated in dusty areas, the
filter element should be replaced more often.
For Diesel engines, the air filter canister should be
cleaned at the same time the filter is replaced.

SERVICE/REPLACEMENT
(1) Remove the air cleaner cover.
(2) Remove the air cleaner filter (Fig. 4).

CAUTION:
Do not tap the filter or immerse the filter medium in liquid to remove trapped debris.
(3) Clean filter by blowing the trapped debris from
the filter with compressed air (Fig. 5). Direct the air in the opposite direction of normal intake air flow.
Keep the air nozzle at least two inches away from
the filter.
(4) If the filter has become partially saturated with

oil,
replace the filter. Inspect the crankcase ventilat­
ing system for proper operation.
(5) Wash the air cleaner cover and body with
cleaning solvent. Wipe it dry.
(6) Install the air cleaner filter element. Attach
the cover to the body (Fig. 4).
Fig,
4
Engine
Air Oeaner—
Typical

•

Fig.
5
Cleaning
Filter
Element—Typical

DIESEL
ENGINE
AIR
FILTER CANISTER MAINTENANCE SCHEDULE

The Diesel engine air filter should be cleaned after
each interval specified in the Diesel engine mainte­
nance schedule.
When the vehicle is operated in dusty areas, the
canister should be cleaned more frequently.

EXHAUST
MANIFOLD HEAT CONTROL VALVE
MAINTENANCE SCHEDULE
The exhaust manifold heat valve should be ser­
viced after the interval specified in the maintenance schedule has elapsed.
SERVICE The exhaust manifold heat valve is located at the
left manifold (Fig. 6). Test the valve for non-re­ stricted movement.
Fig.
6 Manifold Heat Control
Valve
LUBRICATION
AND
MAINTENANCE
0 - 17

Fig.
7 Positive
Crankcase
Ventilation

System—Typical

SYSTEM OPERATION
Each PCV system is comprised of an air inlet filter,
a flow-control (PCV) valve, and the associated hoses.
The air inlet filter is located at the cylinder head cover (Fig. 7).
WARNING:
USE
EXTREME CAUTION WHEN
THE

ENGINE
IS
OPERATING.
DO NOT PUT
YOUR
HANDS NEAR
THE
DRIVE BELT(S), PULLEYS
OR

FAN BLADE.
DO NOT
STAND
IN A
DIRECT LINE

WITH
THE FAN
BLADE.

(1) With the engine idling, accelerate momen­
tarily. The valve shaft counterweight should move CLOCKWISE.
(2) If no movement is observed, either the shaft is
binding or the thermostat spring is weak or broken. (3) If the thermostat spring is weak or broken, re­
place the spring.
(4) Verify the manifold is COOL. Apply
MOPAR®Rust Penetrant (or an equivalent product)
to each end of the valve shaft at the bearings (Fig.
6).

(5) Allow the solvent to penetrate for a few min­

utes.
Then, rotate the valve shaft back and forth un­
til it turns without restriction.

AIR INJECTION SYSTEMS/AIR PUMP
Air injection system/air pump valves and switches
should be periodically tested for proper operation. In­
spect the check valve tubing for corrosion. Replace it
if excessive corrosion exists.

CRANKCASE
VENTILATION
SYSTEM
All gasoline engines are equipped with a positive
crankcase ventilation (PCV) system. The PCV sys­
tem prevents emission of residual engine oil vapor
from the crankcase (Fig. 7).

0-18
LUBRICATION
AND
MAINTENANCE

• MAINTENANCE SCHEDULE
A crankcase ventilation system must be clean to
provide good operation and durability. Periodic main­
tenance is necessary. Replace the PCV valve. Re­
move residual combustion deposits from the hoses and throttle body/intake manifold passages.
The PCV valve should be replaced and the system
should be serviced at the interval specified in main­
tenance schedule. If a vehicle is routinely used for short trips, the crankcase ventilation system could
possibly require more maintenance.
CRANKCASE AIR INLET FILTER
MAINTENANCE SCHEDULE Replace or clean, the air inlet filter at the interval
specified in maintenance schedule.
More frequent PCV system maintenance could be
required for:
• Vehicles routinely used for short trips
• Vehicles routinely involved in stop and go traffic
operation
• Vehicles routinely involved in extended periods of
engine idle
MAINTENANCE Clean and lubricate the crankcase air inlet filter
according to the following procedure. (1) Disconnect the fresh air hose from the port on
the crankcase air inlet filter housing (Fig. 8).
(2) Remove the air filter housing from the cylinder
head cover (Fig. 8). Clean the filter in kerosene or a similar solvent.
(3) Lubricate the filter by inverting the housing
and filling it with SAE 30 viscosity engine oil.
(4) Insert the air filter housing nipple in the cylin­
der head cover grommet. Connect the fresh air hose
to the upper port (Fig. 8).
J9000-52

Fig.
8
Crankcase
Air Inlet
Filter
THROTTLE CONTROL LINKAGE

Transmission linkage pivot pin areas (Fig. 9),
should be serviced. The areas lubricated every second
oil change with a multi-purpose lubricant (NLGI GC-
LB).

PIVOT
AREAS
Fig.
9
Transmission
Linkage
Pivot Areas

FUEL
SYSTEM

INSPECTION The fuel system filler cap, nozzle, tubes, hoses, and
connections should be inspected periodically.
FUEL FILTER The fuel filter requires service only when a fuel
contamination problem is suspected. For proper diag­
nosis and service procedures refer to Group 14, Fuel
System.
GASOLINE ENGINE FUEL REQUIREMENTS All gasoline engines require fuel that has a mini­
mum octane rating of 87 determined by the (R +
M)/2 calculation method.
The use of a brand of unleaded gasoline that con­
tains additives is recommended. Gasoline with addi­
tives will improve fuel economy and reduce emissions.

ALCOHOL/GASOLINE
BLENDS
Many brands of blended unleaded gasoline am now
available. Unleaded gasoline is blended with oxygenated-type
fuels to produce a clean air gasoline in many areas.
The use of this type of blended fuel is recommended.
ETH ANOL—Unleaded gasoline and ethanol
blended fuels are a mixture of 10 percent ethanol and 90 percent unleaded gasoline. This is an accept­
able blend of fuel.
MTBE— MTBE blended fuels are a mixture of un­
leaded gasoline and up to 15 percent MTBE (Methyl
Tertiary Butyl Ether). Unleaded gasoline blended
with MTBE is acceptable.