The information on this page is listed in the following order:
- Common Design
- Dimensions
- Body
- Engines
- Transmissions
- Transfer Cases
- Driveshafts
- Axles
- Gearing
- Cooling System
- Airbags
- Production Numbers
- Trim Levels
- Control Arm Length Chart
- FAQ
Common Design
All XJs were built as a "Unibody" design with the body and frame rails tied together as one piece as opposed to a body on frame design. All XJs have solid axles front and rear. The suspension consists of coils for the front and leaf springs for the rear. All XJs came with disc brakes in the front and drums in the rear.
Dimensions
(small differences may occur depending on optional equipment or trim level)
Body
The body comes in both 2-door and 4-door styles with a rear hatch (liftgate).
Engines
Manual Transmissions
Automatic Transmissions
Transfer Cases
The transfer cases used are all chain driven with aluminum housings. NP stands for "New Process" which is the brand, if you will. The newer ones are NV instead which stands for "New Venture". It is the same transfer case just a different name.
Driveshafts
Front Axles
Rear Axles
(Dana 35 axles are sometimes referred to as Dana 35C - The "C" does not stand for c-clip. It stands for "custom" meaning it came from Dana unfinished.)
(8.25 axles - none of these axles were used on XJs with ABS brakes. If you have ABS, you have the Dana 35. Without ABS you could have either axle. 8.25 axles are c-clip)
Gearing
Cooling Systems
Airbags
Production Numbers
# of XJs built in given year:
Trim Levels
Control Arm Length Application Chart
Stock 15.75 15 ¾ 15.00 15
2” 15.92 16 14.88 15
3” 16.09 16 14.92 15
4” 16.33 16 3/8 15.03 15
4.5” 16.47 16 ½ 15.11 15
5” 16.62 16 5/8 15.21 15 ¼
6” 16.97 17 15.44 15 ½
7” 17.36 17 3/8 15.74 15 ¾
8” 17.81 17 ¾ 16.09 16
9” 18.30 18 ¼ 16.50 16 ½
10” 18.82 18 ¾ 16.96 17
FAQ
This mostly applies to XJ's, but most will also apply to the cousin of the XJ called the MJ or Comanche. This is not meant to guide people to change, alter or modify any current setups, planned setups, or the way you do things. This is strictly meant to be a list of suggestions that has been gathered by people who feel their experience with these vehicles is enough to warrant posting such information to help out new jeepers or any person who is seeking answers to some common questions typically asked..
Common Abbreviations
Body (armor, problems, tow points)
** Use the proper mounting hardware with brackets that are professionally built, this very important.
Driveline
Engines
Several things can cause overheating…
Lifts (tire fitting, backspacing, lift types)
--No trimming and no lift, factory wheels:
Typically a stock rig can handle 29" tires, MAYBE 30"
-- No trimming, 15x8" Tech1 w/4.75 backspacing:
2" lift = 29 to 30x9.50 tires
3" lift = 30x9.50 tires
4.5" lift = 31x10.50 tires
-- Minor trimming, 15x8" Tech1 w/4.75 backspacing:
2" lift = 30x9.50 tires
3" lift = 30x9.50 to 31x10.50 tires
4.5" lift = 31x10.50 to 32x11.50 tires
6" lift = 33x12.50 tires
--In addition to these guidelines, year must be considered. Up to 96 the wheel wells were generally more "open"…97 and later have a tighter front wheel well and are more likely to experience rubbing. Of course, virtually any tire can be fit with enough trimming. Typically most XJ owners don't go much larger than 35" tires, and that's at a minimum of 6" of lift.
If your wheel backspacing is less than 4.75" (such as 3.75") expect to add at least an extra inch of lift.
Also, thinner tires will fit easier as well. (such as 33x10.50's)
Vibes
Will I get vibes after my lift? Do I need a SYE?
This is not a cut and dry question/answer. The safest answer is: wait and see. Prepare ahead of time, have enough money saved to buy a slip yoke eliminator in case you end up needing it. Of course it's always ideal to get one, but sometimes people can't afford it. That being said, here are the options:
A BIG thanks goes out to the several people who helped compile the gold mine of information on this page.
All XJs were built as a "Unibody" design with the body and frame rails tied together as one piece as opposed to a body on frame design. All XJs have solid axles front and rear. The suspension consists of coils for the front and leaf springs for the rear. All XJs came with disc brakes in the front and drums in the rear.
Dimensions
(small differences may occur depending on optional equipment or trim level)
- wheelbase = 101.4"
- overall length = 165.3" - 168.8"
- overall width = 67.9" - 70.5"
- track = 58"
- height = 64"
- height with roof rack = 66.8"
- ground clearance (from differentials) = 7.3" - 8.3"
- approach angle = 37.6* - 38*
- departure angle = 31* - 32.1*
- breakover angle = 21* - 21.9*
- curb weight 2wd = 2,891 lbs - 2,993 lbs
- curb weight 4wd = 3,057 lbs - 3,386 lbs
- cargo capacity = 71.0 cu ft.
Body
The body comes in both 2-door and 4-door styles with a rear hatch (liftgate).
- In 94 side-impact beams were added in the doors and roof was strengthened. The 3rd brakelight was added to the top of the liftgate.
- In 96 the body structure was strengthened some although it was not noticeable in appearance.
- In 97 the body (and interior) was redesigned to freshen it up a bit. Most noticeably it gave the body smoother lines by changing the bumpers, flares, and moldings. The front fender was trimmed just below the headlights and replaced with plastic bumper endcaps that wrap around to the wheel well. The liftgate was also changed from fiberglass to sheet metal in this year. The windshield washer bottle was also moved to the inside of the drivers side front fender.
Engines
- 2.5L I4 carburated - 105 hp @ 5000 rpm, 132 ft lb torque @ 2800 rpm - used in 84-85 models
- 2.5L I4 TBI (fuel injected) - 117 hp @ 5000 rpm, 135 ftlb @ 3500 rpm - used in 86 and updated in 87-90 to 121hp
- 2.5L I4 MPI (multi-port injection) - 130 hp @ 5250 rpm, 139 ft lb @ 3250 rpm - used in 91-00
- GM 2.8L V6 - 115 hp @ 4800 rpm, 145 ft lb @ 2400 rpm - used in 84-86
- Renault 2.1L 4cyl. Turbo Diesel - 85 hp @ 3750 rpm, 132 ft lb @ 2750 rpm - used in 85-87
- Italian VM 2.5L Turbo Diesel - 140 hp, 236 ft lb torque - used in overseas XJs
- 4.0L I6 "Power Tech" - 177 hp @ 4750 rpm, 220 ft lb @ 4000 rpm - used 87-90
- 4.0L I6 MPI "Power Tech HO" (High Output) - 190 hp @ 4750 rpm, 220 ft lb @ 4,000 rpm - used in 91-95 and updated in 96-01 to 225 ft lb torque @ 3000 rpm (00-01 models use a distributorless ignition system)
Manual Transmissions
- T4 or a T5 may have been used instead of an AX4 or an AX5 due to supply shortages.
- AX4 - 4 speed manual - manufactured by Aisin - used 84-86 with 2.5L I4 and 2.8L V6 engines
- AX5 - 5 speed manual - manufactured by Aisin - used with 2.8L V6 and 87+ with 2.5L I4
- BA10/5 - 5 speed manual - manufactured by Peugot - used only up to 89
- AX15 - 5 speed manual - manufactured by Aisin - used with 4.0L I6 engines
- NV3550 - 5 speed manual - manufactured by New Venture - used in 00-01 in SE models with 4.0L I6 engines
Automatic Transmissions
- Torqueflight 904 - 3 speed automatic - used 84-86 with 2.8L V6 engine
- 30RH - 3 speed automatic - used with 2.5L I4 engine
- AW4 - 4 speed automatic, electronically controlled - manufactured by Aisin - used from 87-01 (87-91 models include a Power/Comfort button that adjusts the shift points)
Transfer Cases
The transfer cases used are all chain driven with aluminum housings. NP stands for "New Process" which is the brand, if you will. The newer ones are NV instead which stands for "New Venture". It is the same transfer case just a different name.
- NP207 - "Command-Trac" part-time only - 2.61:1 ratio low range - used 84-87
- NP231 - "Command-Trac" part-time only - 2.72:1 ratio low range - shift pattern 2H - 4H - N - 4L - used 87-01
- NP228/NP229 - "Selec-Trac" - 2Hi - 4Hi(full-time) - N - 4Lo (part-time) - used 84-87
- NP242 - "Selec-Trac" part-time OR full-time - 2.72:1 ratio low range - shift pattern 2wd - 4part-time - 4full-time - N - 4LO - used 87-01
Driveshafts
- Front - From 84 thru 86 the front driveshaft was a true CV style ("beer can on a popsicle stick"), 87 + The front is a "double cardan" two-piece driveshaft with a CV joint at the transfer case end.
- Rear - The 228 and 229 transfer cases used a fixed output yoke, with a 2-piece driveshaft incorporating the slip spline. Otherwise, The rear is a one-piece shaft with standard u-joints at both ends. The slip yoke is located on the output shaft of the transfer case. On 84-95 models, the yoke slides in and out of the transfer case and is lubricated by the ATF fluid internally. On 96-01 due to a design change, the slip yoke is external (does not slide in and out of the transfer case). This slip yoke is covered with a rubber boot.
Front Axles
- Dana 30 high pinion - reverse cut - 27 spline, 1.16" diameter shafts, 7.13" ring gear - used 84-99 (some axles through 91 are vacuum disconnect, 92+ are non-disconnect, 89-95 with ABS have 5-297x u-joints, all 95+ have 5-297x u-joints, all others have 5-260x u-joints except 84 thru 86 they were CV type rather than open u-joints)
- Dana 30 low pinion - standard cut - 27 spline, 1.16" diameter shafts, 7.13" ring gear, 5-297x u-joints - used 00-01
Rear Axles
(Dana 35 axles are sometimes referred to as Dana 35C - The "C" does not stand for c-clip. It stands for "custom" meaning it came from Dana unfinished.)
(8.25 axles - none of these axles were used on XJs with ABS brakes. If you have ABS, you have the Dana 35. Without ABS you could have either axle. 8.25 axles are c-clip)
- Dana 35 non c-clip - 27 spline, 1.18" diameter shafts, 7.58" ring gear, 2.62" axle tube - used 84-89
- Dana 35 c-clip - 27 spline, 1.18" diameter shafts, 7.58" ring gear, 2.62" axle tube - used 90-01
- Chrysler 8.25 - 27 spline, 1.17" diameter shafts, 8.25" ring gear, 3" axle tube - used 91-96
- Chrysler 8.25 - 29 spline, 1.21" diameter shafts, 8.25" ring gear, 3" axle tube - used 97-01
- Dana 44 non c-clip - 30 spline, 1.31" diameter shafts, 8.5" ring gear, 2.75" axle tube - used 87-89 on XJs equipped with towing package.
Gearing
- 3.07 - used with 4.0L engine / manual transmission
- 3.31 - only available on older 2 door XJs with the "Fuel Economy" package
- 3.55 - used with 4.0L engine with automatic transmission; also used with 2WD 4-cyl engines (possibly 4WD as well) equipped with the 4-speed manual transmission
- 3.73 - found in some XJs with the towing package
- 4.10 - used with 2.5L engine usually, and older XJs with the "Off-Highway Vehicle" package.
Cooling Systems
- Open style - any normal cooling system used today. Opposite of closed style described below.
- Closed style - has no radiator cap and utilizes a pressure bottle. This style cooling system was used in 87-90 XJs.
Airbags
- Drivers side airbag (mechanical) was added in 95.
- Passenger side airbag was added in 97. Airbags changed from mechanical to electronic in this year also.
Production Numbers
# of XJs built in given year:
- 84 - 93,326
- 85 - 120,328
- 86 - 107,225
- 87 - 139,295
- 88 - 187,136
- 89 - 207,216
- 90 - 151,230
- 91 - 151,578
- 92 - 137,826
- 93 - 144,961
- 94 - 123,391
- 95 - 120,234
- 96 - 286,463
- 97 - 258,958
- 98 - 182,845
- 99 - 186,116
- 00 - 165,590
- 01 - 120,454
Trim Levels
- 84 - Base, Wagoneer, Pioneer, Chief
- 85 - Base, Wagoneer, Pioneer, Chief, Laredo
- 86 - Base, Wagoneer, Pioneer, Chief, Laredo
- 87 - Base, Wagoneer, Pioneer, Chief, Laredo, Limited
- 88 - Base, Wagoneer, Pioneer, Chief, Laredo, Limited, Sport
- 89 - Base, Wagoneer, Pioneer, Chief, Laredo, Limited, Sport
- 90 - Base, Wagoneer, Pioneer, Chief, Laredo, Limited, Sport
- 91 - Base, Briarwood, Chief, Laredo, Limited, Sport
- 92 - Base, Briarwood, Chief, Laredo, Limited, Sport
- 93 - Base, Sport, Country
- 94 - SE, Sport, Country
- 95 - SE, Sport, Country
- 96 - SE, Sport, Classic, Country
- 97 - SE, Sport, Classic, Country
- 98 - SE, Sport, Classic, Limited
- 99 - SE, Sport, Classic, Limited
- 00 - SE, Sport, Classic, Limited, Freedom
- 01 - Sport, Limited, 60th Anniversary Edition
Control Arm Length Application Chart
- Lower Arms Upper Arms
Stock 15.75 15 ¾ 15.00 15
2” 15.92 16 14.88 15
3” 16.09 16 14.92 15
4” 16.33 16 3/8 15.03 15
4.5” 16.47 16 ½ 15.11 15
5” 16.62 16 5/8 15.21 15 ¼
6” 16.97 17 15.44 15 ½
7” 17.36 17 3/8 15.74 15 ¾
8” 17.81 17 ¾ 16.09 16
9” 18.30 18 ¼ 16.50 16 ½
10” 18.82 18 ¾ 16.96 17
FAQ
This mostly applies to XJ's, but most will also apply to the cousin of the XJ called the MJ or Comanche. This is not meant to guide people to change, alter or modify any current setups, planned setups, or the way you do things. This is strictly meant to be a list of suggestions that has been gathered by people who feel their experience with these vehicles is enough to warrant posting such information to help out new jeepers or any person who is seeking answers to some common questions typically asked..
Common Abbreviations
- AT = Automatic Transmission OR All-Terrain
- MT = Manual Transmission OR Mud-Terrain
- TC = Transfer Case OR Torque Converter
- SYE= Slip Yoke Eliminator (also called a fixed-yoke conversion or a short shaft kit)
- SA = Solid Axle
- SFA= Solid Front Axle
- SRA= Solid Rear Axle
- CA = Control Arm
- LCA= Lower Control Arm
- UCA= Upper Control Arm
- IFS= Independent Front Suspension
- IRS= Independent Rear Suspension
- SOA= Spring Over Axle
- SUA= Spring Under Axle
- BPE= Bar Pin Eliminator
- DPA= Drop Pitman Arm
- ECU= Engine Control Unit
- TCU= Transmission Control Unit
- TB = Throttle Body
- FI = Fuel Injection
- MPI= Multi-Port fuel Injection
- TPS= Throttle Position Sensor
- IAS= Idle Air Stepper motor
- CPS= Crankshaft Position Sensor
- MAP= Manifold Absolute Pressure (sensor)
- O2 = Oxygen (sensor)
- NSS= Neutral Safety Switch (sometimes called Neutral Start Switch)
Body (armor, problems, tow points)
- Why can't my XJ have a body lift?
- How can I mount tow hooks on the front of my XJ?
** Use the proper mounting hardware with brackets that are professionally built, this very important.
- What's a nutstrip?
- Why is my hood stuck shut?!
Driveline
- What's the difference between a 231 and a 242 transfer case?
- What's the difference between a locker and a limited slip?
- What is Axle wrap?
Engines
- Why does my motor overheat?
Several things can cause overheating…
- Bad thermostat (it may stick and not allow the engine to cool)
- Bad electric fan motor or sensor (this should kick on once the vehicle reaches 220 degrees, if it doesn't…it's bad)
- Bad clutch fan (this is designed to spin on a clutch system, if it fails you will overheat in the city very quick)
- Bad radiator (plugged or broken fins will cause an XJ to overheat)
- Plugged coolant passages in the engine block. (typically manifested by highway overheating)
- Why won't my Jeep start?
- Why won't my reverse lights work?
- Why is there oil in my air filter box?
Lifts (tire fitting, backspacing, lift types)
- What size tires can I fit on my Jeep?
--No trimming and no lift, factory wheels:
Typically a stock rig can handle 29" tires, MAYBE 30"
-- No trimming, 15x8" Tech1 w/4.75 backspacing:
2" lift = 29 to 30x9.50 tires
3" lift = 30x9.50 tires
4.5" lift = 31x10.50 tires
-- Minor trimming, 15x8" Tech1 w/4.75 backspacing:
2" lift = 30x9.50 tires
3" lift = 30x9.50 to 31x10.50 tires
4.5" lift = 31x10.50 to 32x11.50 tires
6" lift = 33x12.50 tires
--In addition to these guidelines, year must be considered. Up to 96 the wheel wells were generally more "open"…97 and later have a tighter front wheel well and are more likely to experience rubbing. Of course, virtually any tire can be fit with enough trimming. Typically most XJ owners don't go much larger than 35" tires, and that's at a minimum of 6" of lift.
If your wheel backspacing is less than 4.75" (such as 3.75") expect to add at least an extra inch of lift.
Also, thinner tires will fit easier as well. (such as 33x10.50's)
- What is backspacing?
- What is wheel offset?
- Offset - The distance from the centerline to the hub mount pad (where the wheel attaches to the hub)
- Positive Offset - The hub-mounting surface is toward the front or wheel side of the wheel
- Negative Offset - The hub mounting surface is toward the back or brake side of the wheels centerline.
Vibes
- What's a SYE?
Will I get vibes after my lift? Do I need a SYE?
This is not a cut and dry question/answer. The safest answer is: wait and see. Prepare ahead of time, have enough money saved to buy a slip yoke eliminator in case you end up needing it. Of course it's always ideal to get one, but sometimes people can't afford it. That being said, here are the options:
- Typically, if you are over 3 inches of lift, you'll need a SYE. Now, that's just typical, not absolute. That is especially true for 1996 and newer XJ's because they have a longer output shaft. This puts more stress on the components and creates more vibes.
- Other options are transfer case drop kits and long travel slip yokes. These typically are more of a "band-aid" than a fix and can sometimes cause more problems in the long run.
- What is Death Wobble?
- What causes Death Wobble?
- Out of balance tires or out of round wheels.
- Loose track bar.
- Worn front-end joints. (tie rod ends, track bar, ball joints, etc)
- Bad alignment.
- Bad caster angle.
- Bad steering stabilizer.
- What causes tire shimmy?
- What is and what causes bump steer?
A BIG thanks goes out to the several people who helped compile the gold mine of information on this page.