1995 JEEP YJ engine

FOREWORD
The information contained in this service manual has been prepared for the professional automotive tech-
nician involved in daily repair operations. This manual does not cover theory of operation, which is addressed
in service training material. Information describing the operation and use of standard and optional equipment
is included in the Owner 's Manual provided with the vehicle.
Information in this manual is divided into groups. These groups contain general information, diagnosis,
testing, adjustments, removal, installation, disassembly, and assembly procedures for the components. To as-
sist in locating a group title page, use the Group Tab Locator on the following page. The solid bar after the
group title is aligned to a solid tab on the first page of each group. The first page of the group has a contents
section that lists major topics within the group. If you are not sure which Group contains the information you
need, look up the Component/System in the alphabetical index located in the rear of this manual.
A Service Manual Comment form is included at the rear of this manual. Use the form to provide Chrysler
Corporation with your comments and suggestions.
Tightening torques are provided as a specific value throughout this manual. This value represents the
midpoint of the acceptable engineering torque range for a given fastener application. These torque values are
intended for use in service assembly and installation procedures using the correct OEM fasteners. When re-
placing fasteners, always use the same type (part number) fastener as removed.
Chrysler Corporation reserves the right to change testing procedures, specifications, diagnosis, repair
methods, or vehicle wiring at any time without prior notice or incurring obligation.
NOTE: The acronyms, terminology and nomenclature used to identify emissions related components in
this manual may have changed from prior publications. These new terms are in compliance with S.A.E.
recommended practice J1930.
NEXT PAGE©

GROUP TAB LOCATOR
Introduction
0Lubrication and Maintenance
2Front Suspension and Axle
3Rear Suspension and Axles
5Brakes
6Clutch
7Cooling System
8Electrical
9Engines
11Exhaust System and Intake Manifold
13Frame and Bumpers
14Fuel System
16Propeller Shafts
19Steering
21Transmission and Transfer Cases
22Wheels and Tires
23Body Components
24Heating and Air Conditioning
25Emission Control Systems
Index
Service Manual Comment Forms (Rear of Manual)

INTRODUCTION
CONTENTS
page page
DESIGNATIONS, LABELS/PLATES, CODES AND
DIMENSIONS.......................... 1MEASUREMENT AND TORQUE
SPECIFICATIONS...................... 11
DESIGNATIONS, LABELS/PLATES, CODES AND DIMENSIONS
INDEX
page page
Engine and Transmission/Transfer Case
Identification............................ 5
International Vehicle Control and Display Symbols . . 5
Major Component Identification................ 5
Trailer Towing Specifications.................. 5
Vehicle Code Plate......................... 4Vehicle Designations........................ 1
Vehicle Dimension Data..................... 5
Vehicle Identification Number (VIN) Plate......... 4
Vehicle Load Data......................... 5
Vehicle Safety Certification Label............... 4
VEHICLE DESIGNATIONS
The Vehicle Code Designations chart lists the vehi-
cle description and code for Cherokee and Wrangler
vehicles. The codes are used to identify vehicle types
in charts, captions and in service procedures. The ve-
hicle codes are different than the Vehicle Identifica-
tion Number (VIN) or the wheelbase/model code.
The following illustrations shows the labels, decals
and plates as well as locations on each vehicle.
VEHICLE CODE DESIGNATIONS
JINTRODUCTION 1

VEHICLE SAFETY CERTIFICATION LABEL
A vehicle safety certification label (Fig. 1) is at-
tached to every Jeep vehicle. The label certifies that
the vehicle conforms to all applicable Federal Motor
Vehicle Safety Standards. The label also lists:
²Gross vehicle weight rating (GVWR) and the gross
front and rear axle weight ratings (GAWR's) based on
a minimum tire rim size and a maximum cold tire
inflation pressure.
²Month and year of vehicle manufacture.
²Vehicle identification number (VIN).
²Type of vehicle.
²Month, day and hour (MDH) of final assembly.
The label is located on the driver-side door shut-
face.
VEHICLE IDENTIFICATION NUMBER (VIN) PLATE
The Vehicle Identification Number (VIN) plate islocated on the lower windshield fence near the left
A-pillar. The VIN contains 17 characters that provide
data concerning the vehicle. Refer to the VIN decod-
ing chart to determine the identification of a vehicle.
The Vehicle Identification Number is also imprinted
on the:
²Body Code Plate.
²Vehicle Safety Certification Label.
²Frame rail.
To protect the consumer from theft and possible
fraud the manufacturer is required to include a
Check Digit at the ninth position of the Vehicle Iden-
tification Number. The check digit is used by the
manufacturer and government agencies to verify the
authenticity of the vehicle and official documentation.
The formula to use the check digit is not released to
the general public.
VEHICLE CODE PLATE
A metal vehicle code plate is attached to the left
(driver) side of the dash panel in the engine compart-
ment (Fig. 2). There can be a maximum of seven rows
of vehicle information imprinted on the plate. The
information should be read from left to right, starting
with line 1 at the bottom of the plate up through line
7 (as applicable) at the top of the code plate.
Refer to the decoding chart to decode lines 1 up
through 3.
Lines 4 through 7 (if used) on the vehicle code plate
are imprinted on the plate (in sequence) according to
the following:
VEHICLE IDENTIFICATION NUMBER (VIN) DECODING
Fig. 1 Vehicle Safety Certification LabelÐTypical
4 INTRODUCTIONJ

²3-character sales code.
²3-digit numerical code.
²6-digit SEC code.
If there is not enough space left in the row for all
of the 6-digit SEC code (if used):
²The unused space will remain blank.
²The code will be listed in the next row.
The last nine positions of row 7 will contain a
2-digit code, when applicable, and a 6-digit gateline
serial number (same as the last 6 numbers of the
VIN).The last code imprinted on a vehicle code plate will
be followed by the imprinted word END. When two
vehicle code plates are required, the last available
spaces on the first plate will be imprinted with the
letters CTD (for continued).
When a second vehicle code plate is necessary, the
first four spaces on each row will not be used because
of the plate overlap.
ENGINE AND TRANSMISSION/TRANSFER CASE
IDENTIFICATION
When required, refer to Group 9, Engines for all
engine identification data. Refer to Group 21, Trans-
missions for all transmission/transfer case identifica-
tion data.
MAJOR COMPONENT IDENTIFICATION
When required, refer to the applicable service infor-
mation group for major component identification
data.
VEHICLE DIMENSION DATA
The vehicle dimension data charts list the exterior
and interior dimensions for each type of Jeep vehicle.
VEHICLE LOAD DATA
The Vehicle Load Data chart lists the following in-
formation:
²Gross vehicle weight rating (GVWR).
²Gross axle weight ratings (GAWR).
²Cargo weight.
²Passenger weight for each Jeep type/body style.
TRAILER TOWING SPECIFICATIONS
The Trailer Towing Specification chart provide:
²Minimum Vehicle requirements.
²The maximum trailer tongue weight.
²The maximum trailer weight.
²The maximum combined weight of the trailer/load/
towing vehicle with a specific engine/transmission/
axle combination.
INTERNATIONAL VEHICLE CONTROL AND DISPLAY
SYMBOLS
Most of the graphic symbols illustrated in the fol-
lowing chart are used to identify various instrument
controls and displays.
Fig. 2 Vehicle Code Plate
VEHICLE CODE DECODING
JINTRODUCTION 5

LUBRICATION AND MAINTENANCE
CONTENTS
page page
CHASSIS AND BODY COMPONENTS........ 28
DRIVETRAIN........................... 22
ENGINE MAINTENANCE................... 15GENERAL INFORMATION.................. 1
JUMP STARTING, TOWING AND HOISTING.... 9
MAINTENANCE SCHEDULES................ 4
GENERAL INFORMATION
INDEX
page page
Classification of Lubricants................... 2
Components Requiring No Lubrication........... 2
Fluid Capacities........................... 3
Fuel Requirements......................... 1International Symbols....................... 1
Introduction.............................. 1
Lubrication and Replacement Parts
Recommendation......................... 2
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.
Additional maintenance and lubrication informa-
tion is listed in the Owner's Manual.
INTERNATIONAL SYMBOLS
Chrysler Corporation uses international symbols to
identify engine compartment lubricant and fluid in-
spection and fill locations (Fig. 1).
FUEL REQUIREMENTS
All gasoline engines require the use of unleaded
gasoline to reduce the potentially harmful effects of
lead to the environment. Also unleaded fuel is neces-
sary to prevent damage to the catalytic converter/O2sensor. The fuel must have a minimum octane rating
of 87 based on the (R + M)/2 calculation method.
CAUTION: UNLEADED FUEL ONLY must be used in
vehicles equipped with a catalyst emission control
system. All vehicles have reminders printed on the
instrument panel below the fuel gauge and on the
fuel filler door. The vehicles also have fuel filler
tubes that are specially designed to accept only the
small-diameter dispensing nozzles. It is illegal to
bypass the design of an unleaded fuel filler tube
and contaminate the fuel system.
Fig. 1 International Symbols
JLUBRICATION AND MAINTENANCE 0 - 1

CLASSIFICATION OF LUBRICANTS
Lubricating fluids and chassis lubricants are clas-
sified according to standards recommended by the:
²Society of Automotive Engineers (SAE)
²American Petroleum Institute (API)
²National Lubricating Grease Institute (NLGI)
ENGINE OIL
API CERTIFICATION MARK
For maximum engine protection during all driving
conditions, install an engine oil that contains the API
Certification Mark (Fig. 2). The API Certification
Mark indicates that the oil is certified to meet the
most critical requirements established by the manu-
facturer.
Conformance to API specifications is determined by
tests that measure the ability of an oil to control:
²Engine wear.
²Bearing corrosion.
²Sludge.
²Varnish.
²Oil thickening.
²Rust.
²Piston deposits.
SAE VISCOSITY GRADE
An SAE viscosity grade is used to specify the vis-
cosity of engine oil. SAE 30 specifies a single viscos-
ity engine oil. Engine oils also have multiple
viscosities. These are specified with a dual SAE vis-
cosity grade which indicates the cold-to-hot tempera-
ture viscosity range.
API SERVICE GRADE CERTIFIED
The API Service Grade specifies the type of perfor-
mance the engine oil is intended to provide. The API
Service Grade specifications also apply to energy con-
serving engine oils.
Use an engine oil that is API Service Grade Certi-
fied or an oil that conforms to the API Service Grade
SH or SH/CD. MOPAR provides engine oils that con-
form to all of these service grades.
GEAR LUBRICANTS
A dual grade is also used to specify the viscosity of
multi-purpose gear lubricants.
The API grade designation identifies gear lubri-
cants in terms of recommended usage.
CHASSIS COMPONENT AND WHEEL BEARING
LUBRICANTS
The chassis and wheel bearing lubricants that are
recommended are identified by the NLGI Certifica-
tion Symbol. The symbol contains a coded designa-
tion. This identifies the usage and quality of the
lubricant.
The letter G within the symbol designates wheel
bearing lubricant. The letter L designates chassis lu-
bricant. When the letters are combined, the lubricant
can be used for dual applications. Use only lubricants
that display the NLGI Certification Symbol (Fig. 3).
LUBRICATION AND REPLACEMENT PARTS
RECOMMENDATION
Jeep vehicles are engineered to provide many years
of dependable operation. However, lubrication service
and maintenance are required for each vehicle. When
necessary, MOPARtbrand lubricants and genuine re-
placement parts are highly recommended. Each MO-
PAR brand lubricant and replacement part is
designed and to provide dependability and long ser-
vice life.
COMPONENTS REQUIRING NO LUBRICATION
There are many components that should not be lu-
bricated. The components that should not be lubri-
cated are:
²Air pumps.
²Generator bearings.
²Distributors.
²Drive belts.
²Drive belt idler pulleys.
²Rubber bushings.
²Starter motor bearings.
²Suspension strut bearings.
²Throttle control cables.
²Throttle linkage ball joints.
²Water pump bearings.
Fig. 2 The API Engine Oil Certification Mark
Fig. 3 NLGI Lubricant Container Certification/
Identification Symbol
0 - 2 LUBRICATION AND MAINTENANCEJ

FLUID CAPACITIES
Fuel Tank
XJ .....................................................76.4 L (20.2 gal.)
YJ(Standard) ......................................56.8 L (15 gal.)
YJ(Optional) .......................................75.7 L (20 gal.)
Engine Oil
2.5L ......................................................3.8 L (4.0 qts.)
4.0L ......................................................5.7 L (6.0 qts.)
Cooling System
2.5L(XJ).............................................9.5 L* (10 qts.*)
2.5L(YJ) ........................................8.5 L** (9.0 qts.**)
4.0L(XJ) ........................................11.4 L* (12.0 qts.*)
4.0L(YJ) ......................................9.9 L** (10.5 qts.**)
* Includes (2.2 L) (2.3 qts) for coolant recovery res-
ervoir.
** Includes (0.9 L) (1.0 qt.) for coolant recovery res-
ervoir.
Automatic Transmission
Dry fill capacity.*
AW4 (XJ-4.0L) ...................................8.0 L (16.9 pts.)
30RH (YJ-2.5L) .................................8.2 L (17.5 pts.)
32RH (YJ-4.0L) .................................8.2 L (17.5 pts.)
*Depending on type and size of internal cooler,
length and inside diameter of cooler lines, or use ofan auxiliary cooler, these figures may vary. Refer to
Group 21, Transmission for proper fluid fill proce-
dure.
Manual Transmission
AX4/5 (4X2) .........................................3.3 L (3.5 qts.)
AX5 (4X4) ............................................3.2 L (3.3 qts.)
AX15 (4X2) ..........................................3.1 L (3.2 qts.)
AX15 (4X4) ......................................3.15 L (3.32 qts.)
Fill to bottom of fill hole.
Transfer Case
SELEC-TRAC 242(XJ) .......................1.4 L (3.0 pts.)
COMMAND-TRAC 231(XJ) ...............1.0 L (2.2 pts.)
COMMAND-TRAC 231(YJ-Man Trans) ..1.5 L (3.25
pts.)
COMMAND-TRAC 231(YJ-Auto Trans) ....1.0 L (2.2
pts.)
Front Axle
MODEL 30 (YJ) ..............................1.65 L (3.76 pts.)
MODEL 30 (XJ) ..............................1.48 L (3.13 pts.)
Rear Axle
MODEL 35 (XJ-YJ) ........................1.6 L (3.38 pts.*)
8-1/4 (XJ) .........................................2.08 L (4.4 pts.*)
* When equipped with TRAC-LOK, include 2
ounces of Friction Modifier Additive.
JLUBRICATION AND MAINTENANCE 0 - 3