I found this online here :FSJ FAQ and I’m keeping a copy of it in the event that the other site disappears.  It has a ton of good info and was were I found my initial start.

The Full-Size Jeep FAQ

Revision 0.9

© 2000 John Jacobs

Table Of Contents

  1. Introduction
    1. What is a Full Sized Jeep?
    2. Jeep Dating Note
    3. Acronyms
    4. About this FAQ
    5. About the Author
    6. Legal Junk
  2. Resources
    1. Web Sites
    2. Bulletin Boards
    3. Mailing Lists
    4. Magazines
  3. Engines
    1. I’m stock, what engine do I have?
    2. How can I boost my stock engine performance?
    3. Can I swap in a …?
  4. Transmissions
    1. I’m stock, what trans do I have?
    2. Can I bolt in a Chevy TH400?
    3. Can I bolt in a 700r4?
  5. Transfer Case
    1. I’m stock, what transfer case do I have?
      1. Dana 20
      2. Dana 21
      3. Borg-Warner 1339
      4. Borg-Warner 1305
      5. NP-208
      6. NP-219
      7. NP-229
      8. NP-228
    2. Can I bolt a GM NP-205 to my AMC TH-400?
  6. Axles
    1. Dana 27
    2. Dana 30
    3. Dana 44
    4. Dana 53
    5. Dana 60
    6. Dana 70
    7. AMC 20
  7. Suspension & Tires
    1. Saggin’ Wagon Syndrome
    2. What fits? What hits?
    3. Spring Over Axle Lift
    4. Shackle Flip
    5. Spring Under Frame
    6. Suspension Lifts
    7. Chevy Front Springs?
    8. Chevy Rear Springs?
  8. Chassis & Electrical
    1. Coffin Rot
    2. Spaghetti Wiring
    3. Rhino Chaser
    4. Wide-Track Cherokees
    5. Body Lifts
    6. Body Mounts
  9. Miscellaneous
    1. Cost of Ownership
    2. Gas Mileage
  10. Acknowledgements

1 Introduction

1.1 What is a Full Sized Jeep?

From the IFSJA site, the official definition is:

>> A "FSJ" is any vehicle produced in North America, carrying the "Jeep"
>> nameplate, with 2 or 4drs, in 2 or  4wd, whose wheelbase does not exceed
>> 132", nor is less than 109", and whose tread width is no more than  63"
>> nor less than 57". This definition is known to include the following
>> models:
>> (*) Cherokee: 1974-1983
>> (*) Wagoneer: 1963-1983
>> (*) Grand Wagoneer: 1984-1991
>> (*) Gladiator and J-series pickup: 1963-1987
>> (*) M-715 Military versions and its derivatives

1.1.1 Wagoneer / Grand Wagoneer

When the Wagoneer debuted on November 14, 1962 it was a
revolutionary design. It boasted technological advances such
as independent front suspension and an overhead cam engine.
By 1964, factory air conditioning was available. The
Wagoneer was always a high-priced luxury off-roader. In the
early years, the Wagoneer was offered as a two-door,
four-door, or panel wagon. The panel wagons are rare, though
a few have found pictures and posted them on the web.

From 1966 through 1969, the Super Wagoneer was available.
This version of the Wagoneer featured a high-power Vigilante
327 engine and Hydramatic automatic transmission. The main
focus of the Super Wagoneer was the luxury interior and
exterior and their super price of almost double a standard

Starting in 1984 until the end of production, the name Grand
Wagoneer was used to distinguish it from the smaller
XJ-based Wagoneer. There have been a number of people who
have reportedly found Grand Wagoneers with 1992 VIN plates.

Chrysler ended production in 1991 when it became apparent
they would have to update the Grand Wagoneer to help it
meet emissions and safety standards. What could have been
had they added EFI, ABS, and air bags? Maybe today there
would be 8.0 liter V-10 or Cummins diesel powered Grand
Wagoneers out on the road!

Rumors keep surfacing that DaimlerChrysler will bring back
the Grand Wagoneer nameplate, but it will never be the same.
The latest rumor was even backed up with an official press
release, only to be retracted. Rumor mills say that Jeep
engineers and management had vehicle development halted when
it became clear that it would not be able to pass the
mini-Rubicon at their proving grounds.

1.1.2 Cherokee

The Cherokee was brought about in 1974 to compete with
vehicles such as the Bronco, Blazer, and Ram Charger. It
started off as a two-door only vehicle, but a four-door
model was added later as a base model to the Wagoneer.

Starting in the middle of the 1975 model year, the Cherokee
became available with a more aggressive trim package.
Wide-track Cherokees used the same (wider) axles and flared
front fenders as the J-truck with flared rear fenders to
match. With the wider axles and fender flares, it can fit
larger tires without fender trimmer than “narrow track”
Cherokees and Wagoneers.

Full-sized Cherokees ended production in 1983, and should
not be confused with the smaller XJ-based Cherokees that
started production in 1984 and continue to this day.

1.1.3 Gladiator / J-Series Pick-Up

The Gladiator truck was the pick-up version of the Wagoneer.
Over the years it followed the Wagoneer closely with its
engine, transmission, and transfer case choices.

One of the most notable appearances of a J-Truck was in the
beginning of the movie Twister. It was the yellow truck
driven by Helen Hunt that was sucked up by the tornado. You
can also play six steps to Kevin Bacon with a Gladiator in

The last year of the Gladiator name was in 1971; all later
pick-ups were given the J-Series name. Chrysler ended
J-Truck production in 1987 due to the fact that they already
had the (at the time not so popular) Dodge trucks. There
have been a number of people who have reportedly found
J-series pick-ups with 1988 VIN plates.

Joe Schaefer explains the J-Series numbering systems:

>> they (Jeep) went to the J-10 and J-20 series in 1974. The 200/300 series
>> ended with 1965 but that's also when the 2000/3000 came out so they had the
>> 200/300 and 2000/3000 series in 65.
>> The 4000 series came out in 70 and ended in 73 with all the other 1000
>> series badges.
>> Keep in mind the earlier 200/300/2000/3000/4000 all referred to wheelbase
>> length and all could be had in 1/2 ton and 3/4 ton models(some 1 tons).
>> Models broke down to 4500/4600/4700/4800 etc. The later J-10/20 referred to
>> GVWR tonnage. All J-10's are 1/2 tons and all 20's are 3/4 tons but the J-10
>> could be had in two different wheelbases. Confusing isn't it? :)

1.1.4 M-715 and Derivatives

The M-715 was a military vehicle based on the same SJ
platform as the civilian versions. It came in many
different varieties, and has a cult following of its own.

1.2 Jeep Dating Note

As you read this FAQ, please note that most dates given are plus or
minus one year. This is due to the fact that Jeep has been notorious
for blurring the lines between production years. It has been generally
found that Jeep would run out their stock from previous model year
before starting to use a new part.

Common examples are people finding Buick “Dauntless” V8s in their
1972 Wagoneers, Grand Wagoneers with 1992 VIN plates when Chrysler
officially ended production in 1991, and J-Series pick-ups with
1988 VIN plates when production officially ended in 1987.

So please, do not send me a nasty-gram with a note telling me that
I am an idiot because I quote that Jeep stopped putting the AMC 401
in FSJs in 1978, and you have a stock 1979 with one. It was just
a cruel joke by Jeep.

1.3 Acronyms

Acronym Description
FSJ Full-Sized Jeep
SJ Jeep designation for Full-Sized Jeeps
CJ Jeep designation for 1946 – 1986 Civilian Jeeps
YJ Jeep designation for 1987 – 1995 Wranglers
TJ Jeep designation for 1997 to Present Wranglers
XJ Jeep designation for 1984 to Present Compact Cherokees
and 1984 to 1991 Compact Wagoneers
ZJ Jeep designation for 1993 – 1998 Grand Cherokees
WJ Jeep designation for 1999 to Present Grand Cherokees
MJ Jeep designation for Comanche pick-ups
DJ Jeep designation for Postal Jeeps
AAL Add-a-leaf
AMC American Motors Corporation
A/T All-Terrain Tire
BW Borg-Warner
BWQT Borg-Warner Quadra-Trac
DSPO Dip Stick Previous Owner (family version)
IFS Independent Front Suspension
IFSJA International Full-Size Jeep Association
M/T Mud Terrain Tire
NOS New Old Stock, stock replacement part
NP New Process, a.k.a. New Venture Gear
NPQT New Process Quadra-Trac
NT Narrow Track, usually in reference to Cherokees
NVG New Venture Gear, a.k.a. New Process
OEM Original Equipment Manufacturer
OHC Overhead Cam
OHV Overhead Valve
QT QuadraTrac, full-time 4×4 transfer case
SOA Spring Over Axle conversion
WT Wide Track, usually in reference to Cherokees

1.4 About this FAQ

This FAQ is intended to provide basic information about
Full-Size Jeeps. The information is targeted at the first
questions that many new Full-Size Jeep owners ask when
joining one of the many on-line mailing lists.

This FAQ’s home is on the author’s home page. It may be mirrored
on any site as long as link to the
original site
is maintained.

1.5 About the Author

I own a 1975 Jeep Wagoneer that I purchased in April 1997. When I
bought the vehicle I did not know much about Full-Size Jeeps, but
after spending a couple of years on various mailing lists and
many hours in the garage I have learned a lot. I decided to write
this FAQ after consistently seeing the same questions over and over
as new members joined the mailing lists. Visit my
home page
if you would like to learn more about my FSJ.

1.6 Legal Junk

I probably should mention that Jeep is a registered trademark of
the DaimlerChrysler Corporation. Although, they are not the first
to own it; it started off as Willys, then Kaiser, then
American Motors Corporation, then Chrysler Corporation, and
finally DaimlerChrysler. What a long strange trip it’s been.

I should also mention that the information provided in this
FAQ is not guaranteed to be accurate. I have done my best to
make sure that I am not spewing garbage, but I can’t claim
that I’ll never be wrong. If you find something wrong, let me
know so that I can clean it up.


2 Resources

Though it seems hard to believe, there is actually a lot of info to
be found about Full-Size Jeeps.

2.1 Web Sites

2.1.1 International Full-Size Jeep Association

The IFSJA is currently the largest
FSJ site on the internet. It is a portal for a message forum, mailing
list, techical library, and a large section of reader’s rides.

2.1.2 Wagoneers.com

John Meister’s pages at Wagoneers.com.

2.1.3 The M-715 Zone

The M-715 Zone is dedicated to the M-715
and its derivatives. It is not so concerned with the civilian FSJ versions.

2.1.4 CFSJA

The CFSJA (Colorado Full-Size
Jeep Association) is an active chapter of the IFSJA. They are hosting the
2002 Full-Size Jeep Invasion in Ouray, Colorado to celebrate the 40th
Anniversary of Full-Size Jeeps.

2.1.5 ANZAC

ANZAC is the Australia
and New Zealand Chapter of the IFSJA.

2.2 Bulletin Boards / Message Forums

2.2.1 International Full-Size Jeep Association

The IFSJA Message Forum is probably the most popular Full Size Jeep
message forum on the internet.

Visit the IFSJA for details on
joining the message forum.

2.3 Mailing Lists

Mailing lists are also known as listservs. In general, a person
adds their e-mail to the mailing list and then is able to send
and receive e-mails to and from others on the list. Most mailing
lists provide a real-time mode in which the user receives all e-mails
on the list individually, or through a digest in which they receive
fewer e-mails that have been condensed into a digest.

2.3.1 International Full-Size Jeep Association

The IFSJA mailing list has recently moved to Yahoo! Groups. It is still the
largest and oldest of the mailing lists.

Visit the IFSJA or go directly to the
Yahoo! Groups page
for details on joining this list.

2.3.2 Wagoneers.com FSJ Digest

Shortly after the IFSJA settled on off-road.com, John Meister had a falling out with
the off-road.com site operators. Not long after, John started up his own list and it
continues on. This list tends to blur the lines between XJ’s and FSJ’s more than
the others do.

Visit Wagoneers.com for details on joining this list.

2.3.3 1FSJ

The 1FSJ list started after the second falling out between IFSJA members and
off-road.com. The 1FSJ list rivals the IFSJA in size and number of posts.
It has no restrictions for attaching pictures or using HTML in messages.

Visit 1FSJ for details on joining this list.

2.3.1 Colorado Full-Size Jeep Association

Email list for Full Size Jeep owners who live in or near
Colorado. Discussions include parts, how-tos, 4-wheeling
trips, and more.

Visit CFSJA for details on joining this list.

2.4 Magazines

2.4.1 FSJ Magazine

A small publication dedicated to FSJ’s. Quarterly printed.
Contact FSJ Magazine
for subscription info. The magazine has now made its first
year of publication.

2.4.2 JP

Dedicated to all Jeeps, it contains many (comparatively)
articles on Full-Size Jeeps. This is due to the fact that
most of the smaller Jeeps frequently steal the beefy FSJ
components for their Jeeps. Also, it seems that many of the
writers have FSJs for tow vehicles.

There has been a decline in Full-Size coverage since the editor
Rick Pewe was moved to 4-Wheel Off-Road.

Contact JP Magazine

2.4.3 4-WheelOff-Road

Now that Rick Pewe is the editor, it seems that they are
starting to do some write-ups about Full-Size Jeeps.

Contact 4 Wheel and Off-Road Magazine


3 Engine

3.1 I’m stock, what engine do I have?

Full-Sized Jeeps were only sold with inline six-cylinder engines, or V8s.

3.1.1 Six Cylinder Tornado 230

Inline six-cylinder with an overhead cam (OHC) design. Standard engine
from start of production until 1965. AMC 232

Replaced the Tornado 230 in 1965 and lasted through 1970. AMC 258

The always popular AMC 258 (4.2L) inline six-cylinder. Became
the only available six-cylinder starting from 1971 to 1987.

3.1.2 Eight Cylinder Vigilante 327

The AMC 327, not a Chevy. Available 1965 through 1968. Dauntless 350

The Buick 350 V8. Available 1969 through 1971. AMC 304

The AMC 304 V8 was only offered in 1971 and 1972. AMC 360

The AMC 360 V8 was available from 1971 until the end of production. AMC 401

The AMC 401 V8 was only available from 1974 through 1978.

3.2 How can I boost my stock engine performance?

Many ways, but I’ll try to provide links to the cheap and easy tricks.

3.3 Can I swap in a …?

Yes, but I’ll try and find info about common swaps and issues.


4 Transmission

4.1 I’m stock, what trans do I have?

4.1.1 Automatic Borg-Warner AS-8F

Available from 1962 to 1965 behind the Tornado 230.

Gear Ratio
1st 2.40:1
2nd 1.47:1
3rd 1.00:1 TH-400

The venerable GM Turbo Hydramatic 400 transmission. The TH-400 was
used from 1965 through 1979. From 1965 through 1972 it had a special
adapter between the TH-400 and Dana 20 transfer case that can be
rare and expensive. TH-400s from 1973 through 1979 had a unique
bell housing to mate to the AMC engines, earlier versions used

Gear Ratio
1st 2.48:1
2nd 1.48:1
3rd 1.00:1 Torque Flite 727

The Chrysler Torque Flite 727 was the automatic
transmission for all AMC 360s from 1980 until the end of production.
It was also used with the AMC 258 with 3.31 axle ratios during the
same period.

Gear Ratio
1st 2.45:1
2nd 1.55:1
3rd 1.00:1
Reverse 2.20:1 Torque Flite 999

The Torque Flite 999 was used behind the AMC 258 with 2.72 axle ratio
from 1982 to 1987. It was not available in the J-20.

Gear Ratio
1st 2.74:1
2nd 1.55:1
3rd 1.00:1
Reverse 2.20:1

4.2 Manual T-86A

Available on early two-wheel drive Wagoneers from start of
production until 1966 with the six-cylinder only.

Gear Ratio
1st 2.57:1
2nd 1.55:1
3rd 1.00:1 T-89

Available from start of production until 1966 with the six-cylinder only.

Gear Ratio
1st ?:1
2nd ?:1
3rd ?:1
Reverse ?:1 T-90

Standard on early four-wheel drive Wagoneers from start of
production until 1965 with the Tornado 230 only.

Gear Ratio
1st 2.80:1
2nd 1.55:1
3rd 1.00:1
Reverse 3.79:1 T-98A

Four-speed manual with unsynchronized low, offered as an option from
start of production until 1968 in the Gladiator. Predecessor to the T-18.

Gear Ratio
1st 6.38:1
2nd 3.09:1
3rd 1.69:1
4th 1.00:1
Reverse 7.44:1 T-85

Available from 1966 until 1969 with the Vigilante 327.

Gear Ratio
1st 2.57:1
2nd 1.55:1
3rd 1.00:1 T-14A

Three-speed manual, used from 1967 through 1969. Not used
with the Vigilante 327.

Gear Ratio
1st 3.10:1
2nd 1.61:1
3rd 1.00:1
Reverse 3.10:1 T-15A

The T-15A is a three-speed transmission, it was available
from 1967 through 1979.

Gear Ratio
1st 2.97:1
2nd 1.55:1
3rd 1.00:1
Reverse 2.97:1 T-18

The T-18A offered a unsynchronized granny-low gear, it was available
from 1969 through 1987. Before 1971 the T-18A was known only as the

Gear Ratio
1st 6.32:1
2nd 3.09:1
3rd 1.69:1
4th 1.00:1
Reverse 7.44:1

The T-18 offered a unsynchronized low gear, it was available
from 1971 through 1975.

Gear Ratio
1st 4.03:1
2nd 2.42:1
3rd 1.41:1
4th 1.00:1
Reverse 2.97:1 T-176

The Tremec T-176 transmission was offered starting in 1980 until
end of production of the J-Truck. It was not available with the J-20.

Gear Ratio
1st 3.52:1
2nd 2.27:1
3rd 1.46:1
4th 1.00:1
Reverse 3.52:1 T-5

The T-5 was offered with the AMC 258 in 1982 and 1983.

Gear Ratio
1st 4.03:1
2nd 2.37:1
3rd 1.50:1
4th 1.00:1
Reverse 3.76:1


4.2 Can I bolt in a Chevy TH400?

Many people ask if a TH-400 found in a Chevy can be swapped in
place of TH-400 found behind the AMC engines of the 70s; the
answer is not without an adaptor. The cases and bolt patterns
are different between the Chevy and AMC versions, but the good
news is that the internals are almost identical.

5.1 Can I bolt in a 700r4?

Many people choose the GM 700R4 overdrive transmission as a
swap candidate behind their AMC V8 engines. It can be done
with an adapter to the engine, but it is costly.

For QuadraTrac equipped rigs, they can be adapted to a 700R4.
The adapter is costly, but it would prevent the need for an
axle swap. It is possible to find 700R4 with passenger-side
front drop transfer cases attached, but they are rare and
would most likely still require a rear axle swap to a centered
differential to prevent driveline vibrations.

For 1980 and later FSJs, the cheapest solution would be find
a 700R4 with an NP-242 already attached. This would be a solid
transfer case with a driver side drop and no additional adaptors.
It would also be possible to swap in the original Jeep version
of the New Process case by swapping in a 23-spline output.

5 Transfer Case

5.1 I’m stock, what transfer case do I have?

5.1.1 Dana 20

The Dana 20 was available from 1962 through 1979. During those
years, it was always available with a manual transmission. From 1965
through 1973 it was available behind the TH400 automatic
transmission. It is a gear driven part-time transfer case with a
2.03 low-range.

5.1.2 Dana 21

The Dana 21 was a Dana 20 with no low-range reduction gear. It was
available from 1962 through 1965 with the AS-8F automatic
transmission and Tornado 230 engine.

5.1.3 Borg-Warner 1339

This unit was used behind all automatic transmissions from 1973 to 1979.
The Borg-Warner 1339 “QuadraTrac” unit uses a 2.57:1 low-range. It
offers full-time four-wheel drive capability with a vacuum
actuated “Emergency Drive” that locks the transfer case into 50/50
torque split mode. It is a chain-driven unit with an aluminum case
that requires special (read: expensive) fluid to allow it to act as
a limited slip differential when not in emergency drive.

A part-time conversion kit is available from Mile Marker that
allows the unit to operate as a part-time transfer case. A 16%
overdrive conversion kit is also available. This allows the use
of standard ATF instead of the QT fluid. It also allows for the use
of locking hubs with the front axle.

5.1.4 Borg-Warner 1305

This is a Borg-Warner 1339 without the low-range unit.

A note from Joe Schaefer explaining a possible reason for the
difference in part numbers:

>> it's the exact same x-case etc except for the bolt up reduction
>> unit. I think all the cases have the 1339 number on them. The only reason I
>> can see for the different reference numbers is that the reduction unit
>> wasn't added on at the assembly line by AMC, it was already added on before
>> the assembly plant got the x-cases.

5.1.5 NP-208

The New Process 208 is a chain-driven, aluminum-cased, part-time
transfer case. It offers a 2.61:1 low-range. It was available from
1980 to 1987 as the Command-Trac.

It was standard with all manual transmissions, and with the
six-cylinder and automatic transmission combination.

5.1.6 NP-219

The New Process 219 replaced the BWQT in 1980 and
remained until 1983. FSJs with the NP-219 were also badged as
Quadra-Trac equipped vehicles.

5.1.7 NP-229

The New Process 229 is a chain-driven, aluminum-cased, full-time
transfer case. It offers a 2.61:1 low-range. It was available from
1981 to the end of production as the Select-Trac, with the
exception of 1986.

The NP-229 is selectable between 2-high, 4-lo, and full-time
4-high. This is possible through the use of a limited-slip
viscous-coupled differential in the transfer-case. Unlike
the BWQT, it does not require the expensive Quadra-Trac fluid
to operate in full-time mode; it uses ATF.

5.1.8 NP-228

The New Process 228 is essentially a NP-229 without the
limited-slip viscous-coupler. It was available only in 1986
as the Selec-Trac.

A note from Ethan Brady explaining the differences between the
NP-228 and NP-229:

>> The 228 t-case was (seemingly) only available on the 1986 Grand
>> Wagoneer. It is the exact same as the 229, except there is no expensive
>> viscous coupler (aka fluid coupler) to burn out if the vehicle is towed
>> incorrectly or run in 4wd only on one driveshaft. It is often thought to
>> be less desirable than a 229 because it DOESN'T have the VC. In theory,
>> just by lifting one wheel, the truck wouldn't move. However, there are
>> no actual real world reports of this, and if you're in such terrain,
>> you'd be in 4 low range, anyway, where the front and rear axles are
>> locked together.

5.2 Can I bolt a GM NP-205 to my AMC TH-400?

The NP-205 has a legend for being bulletproof, even more than an Atlas 2
(but it does not have as low of a low-range). The GM NP-205 requires
a passenger side front differential and a centered rear differential.
It can be mounted on an AMC TH-400, but you need…

1) centered rear axle. You might get away with using the stock
Dana 44, but chances are you will have vibrations from the
angle of the driveshaft.

2) GM TH-400 with attached NP-205 and linkage. If they are separated make
sure you have all the parts and that they mate up. There were
different numbers of output shaft splines used for different
applications. In some areas, this is somewhat of an uncommon
combination to find; or it can be pricy. It was available from
1979-85 in 3/4 and 1-ton GM trucks. Later models of the NP-205
went to an aluminum tailshaft and rear slip yoke, which is not
as durable as the fixed yoke applications.

3) New driveshafts

And then you will need to..

1) Swap the GM tailshaft and adapter to your preferably
freshly rebuilt AMC TH-400 and mount the NP-205

2) Modify cross-member as necessary to mount NP-205

3) cut a hole in your floor for the shift linkage

4) Install drive shafts, new axle, and figure out
any of the small details left out of this

5) Possibly move the gas tank or at least clearance
the gas tank skid for the centered rear driveshaft


6 Axles

6.1 Dana 27

Wagoneers used the Dana 27-A from the start of production until 1970.
From 1962 to 1965 the Dana 27 was used in an independent front suspension
using torsion bars.

6.2 Dana 30

Wagoneers used the Dana 30 from 1971 through 1973.

6.3 Dana 44

The Dana 44 was used by FSJs from the start until the end of production.
There was not a year that a Dana 44 was not used on at least one of
the variants on either the front or rear axle.

The Gladiator / J-Series pick-up used the Dana 44 as its front axle
during its entire production span. The Wagoneer went to the Dana 44
in 1974. 1973 and earlier Dana 44s are closed knuckle,
all Dana 44s after 1974 are open knuckle with a six-lug bolt pattern.
In 1983 and 1984, the front Dana 44 hubs were vacuum-actuated.
From 1962 to 1965, the Dana 44 was available in an independent
front suspension using torsion bars.

The Dana 44 was the light-duty rear axle on all FSJs from the start of
production until 1979, and from late 1986 until the end of production.

6.4 Dana 53

The Dana 53 was a semi-floating axle used on heavy half-ton
Gladiators from the start of production until 1968.

6.5 Dana 60

The Dana 60 was the heavy-duty rear axle used on Gladiators and
J-Series pick-ups from 1969 until the end of their production.
There were two major variations produced.

The Dana 60-2 is a semi-floating axle with a five-lug bolt pattern.
It replaced the Dana 53 and was available from 1969 through 1973.
It was used in the 6000 GVWR (still a 1/2 ton) trucks.

The Dana 60-3 is a full-floating axle. It was available on
Gladiators with a six-lug pattern from 1969 to 1973. It was
available on J-20s with an eight-lug pattern from 1974 through the
end of J-Series production.

6.6 Dana 70

The Dana 70 was used as the rear axle for dual-wheel
equipped Gladiators from the start of production until 1969.
It has a six-lug pattern.

6.7 AMC 20

From 1980 through 1986 the AMC model 20 was the light-duty
rear axle on all FSJs. The AMC 20 is a semi-floating rear
axle that has a slightly larger ring gear than a Dana 44. Unlike
the maligned two-piece CJ version, the axle shafts are
one-piece units.


7 Suspension & Tires

Questions about suspension and tires are quite possibly the most
common on any of the mailing lists. See also the
Body Lift section.

The first years of FSJs had independent front torsion bar
suspension with leaf springs as an option for heavy duty applications.

7.1 Saggin’ Wagon Syndrome

Very common on FSJs, especially Wagoneers and Cherokees, is the
Saggin’ Wagon syndrome. Since all are at least ten years old, and
many are much older than that, the rear springs are old and
starting to loose their arch. Many times, an add-a-leaf or a leaf
from another FSJ spring pack can bring it back to level.

Many also lean to the driver’s side, most likely due to the
location of the gas tank and a lot of time with the owner driving
solo. Some will only add an extra leaf to this spring pack to bring
it back to even keel.

7.2 What fits? What hits?

This section describes how much lift and or fender trimming is
needed to fit what size tire. There are no hard and fast rules
as to what is needed, but this is generally what most people find
when trying to upgrade the tires on their FSJ.

The width and backspacing of the wheel used can cause minor
variations in rubbing and not rubbing. From personal experience,
my 31×10.5 A/Ts on 15×7 wagon wheels did not rub nearly as
bad as my 31×10.5 M/Ts on 15×8 wagon wheels. The A/Ts could stuff
in rears and would only mildly rub in the front, and only when
turning. The M/Ts on the wider rim would rub during extreme
articulation and not turning. This is on a 1975 Wagoneer with
about two inches of lift over stock.

When fitting larger tires on an FSJ it may also be necessary to
adjust the steering stops to prevent rubbing on the springs and
inner fenders while turning. Although it will limit suspension
up-travel, extended bump stops can also prevent rubbing during
extreme articulation.

A very comprehensive list was made by River Beast with the help
of many others on the IFSJA forum in the Topic of the Month section.

7.2.1 Wagoneers, Narrow-Track Cherokees

Wagoneers and “Narrow-Track” Cherokees come from the factory with
standard width axles and no fender flares unlike the Wide-Track
Cherokees and J-Series pick-ups. This limits the width of tires
that will fit into the wheel wheels.

Tire Description
30 x 9.5 Stock suspension: no rubbing
31 x 10.5 Stock suspension: may rub during extreme articulationLifted 3″+: no rubbing reported
33×12.5 Lifted 4″+: rubbing during extreme articulationTrimmed fenders + 3″ lift: no rubbing
35×12.5 Lifted 7″+: rubbing during extreme articulationTrimmed fenders + 7″ lift: no rubbing(4″ suspension lift with 3″ body lift)

7.2.2 J-Series Pick-Ups and Wide-Track Cherokees

J-Series pick-ups and “Wide-Track” Cherokees ride on wider
axles and have a larger fender flare than Wagoneers and
Narrow-Track Cherokees. The easiest way to identify
wide-track FSJs is by the larger fender flares that come
with the vehicle.

Tire Description
31 x 10.5 Stock suspension: no rubbing
33 x 12.5 Lifted 3″+: no rubbing
35 x 12.5 Lifted 4″+: rubbing during extreme articulationTrimmed fenders + 4″ lift: no rubbing

7.3 Spring Over Axle Lift

For the mechanically gifted, FSJs offer the opportunity to gain
five or more inches by performing a Spring Over Axle (SOA)
conversion. A SOA conversion entails moving the stock front springs
from their original location under the axle to new spring perches
on top of the axle.

Complications with SOA conversions include the skill required to
weld new spring locators on axle tubes and maintaining proper
steering geometry. It should generally be left to highly skilled
fabricators due to the risks of injury or death in case of a

7.4 Shackle Flip

A lift of approximately two inches can be had on the rear axle by
flipping the rear shackle. Depending on the year of the FSJ, the
rear shackle may or may not be boxed. The shackle is flipped to
locate the springs under the shackle to frame mount, rather than
above it.

Complications of a shackle flip are that if no precautions are made
the shack may re-flip, losing the lift; plus, the shackle flip will
cause a change in the pinion angle between the transfer case and

7.5 Spring Under Frame

A lift for the rear-end of most FSJs, except those that came with it
stock, is to move the rear springs from the side of the frame to
under the frame. At the same time, a buggy-leaf configuration could
also be added for even more flexibilty.

Complications of a spring under frame are moving (welding) the spring
perches and possibly the shock mounts on the rear axle, as well as
the possible need to modify or interference with the gas tank skid plate.

7.6 Suspension Lifts

Here are some of the manufacturers of lift kits for FSJs. Most are
available for 1974 and later applications.

NOTE FOR 1974 AND 1975 FSJs: Although some manufacturers claim they
sell rear springs for all 1974 and later FSJs, owners of 1974 and
1975 Cherokees, Wagoneers, and short-wheelbase J-trucks cannot
use these springs. This is due to the fact that the rear springs are
about 4″ shorter than on the 1976 and later FSJs. You will have to use a
lift block, add-a-leaf, or purchase custom springs. Owners of 1974 and 1975
131″ wheelbase, 7200lb GVWR J-trucks can use the 1976 and later rear
replacement springs.

7.6.1 BDS

Relatively new to the game, they offer a 4″ total spring
lift or 4″ front spring and 3″ rear block.

Contact BDS Suspension

7.6.2 ESPO Springs ‘n Things

ESPO does not make lift kits, but they do have a good
reputation on the IFSJA list for helping out FSJers.

Contact ESPO Springs ‘n Things

7.6.3 National Spring

Though they don’t make a lift kit, they do custom work and
have a great reputation for making custom springs to any size.

National Spring Co.

1402 N. Magnolia Ave.

El Cajon, CA 92020


7.6.4 Rancho

Rancho offers add-a-leafs that provides 2.5 inches of lift.

Contact Rancho

7.6.5 Rough Country

Rough Country offers a 3″ total spring lift or 3″ front
springs and blocks and/or add-a-leafs for the rear.

Contact Rough Country

7.6.6 Rusty’s Off-Road Products

Rusty offers many choices for late model Full-Size Jeep owners from
Add-a-leaf to a 6″ spring lift.

Contact Rusty’s Off-Road Products

7.6.7 Skyjacker

Skyjacker offers a 4″ total spring lift or 4″ front springs
and blocks and/or add-a-leafs for the rear.

Contact Skyjacker

7.6.8 Superlift

Superlift offers a 4″ total spring lift or 4″ front springs
and blocks and/or add-a-leafs for the rear.

Contact Superlift

7.6.9 Trailmaster

Trailmaster offers 4″ front springs.


420 Jay Street

Coldwater, MI 49036


7.6.10 Warn

Warn used to offer their Black Diamond 4″ front spring lift and 4″ rear
block. The kit version also included Warn Black Diamond shocks. Warn
recently decided to leave the suspension business, so this lift is
no longer available unless you find one sitting on a shelf somewhere.

7.7 Chevy Front Springs?

The talk of installing the front springs from a 1973-87 Chevy
pick-up was a popular topic after a mention in JP Magazine.

A quote from Scott Probert from a post of the IFSJA forum:

>> well today i did accomplish installing a set of chevy front rancho 4"
>> lift spings on my grand wag. the springs are 46" long, bout the same as
>> stock springs. since a stock chevy has the weird negative arch thing, the
>> 4" spring only lifted the front about 2 inches,and it also moved the
>> axle forward an inch,which should be a good thing,since i have rubbing at
>> the rear of the inner fender at full stuff.
>> i had to spread the shackles and hangers out just a little, cause the
>> bushings i used made them a little fatter,but they more or less bolted
>> right on. cept now my front driveshaft, which was barely long enuff
>> before, is now too short. it will definately be too short when i replace
>> the 4" springs with tuff country 6" springs

7.8 Chevy Rear Springs?

For those with a wish for more articulation in the rear,
install long 1988-98 half-ton Chevy rear springs in
place of the stock springs. They are about 63 inches long,
making them almost 10 inches longer than 1976 and
later FSJ rear springs. New mounts would have to made up. This
has been done by scoutgrl on the IFSJA forum as well as locating
the rear axle three inches back to allow for fitting of larger

It may also be possible to direct swap rear springs from 1973-87 Chevy pick-up.
They are 56 inches long, compared to approximately 54 inches for 1976
and later FSJs. Scott Probert is planning to do this, I will
add his feedback when he gets it done.


8 Chassis & Electrical

8.1 Coffin Rot

It is very common that mud, leaves, road kill, etc. will become
lodged between the frame rail, gas tank, and gas tank skid plate.
This provides a common rust point for the frame to rot. Many owners
have had to weld in repair plates to this location of the frame.

8.2 Spaghetti Wiring

It is not uncommon to have wiring from the factory that looks like
a DSPO had destroyed it. Due to the elegant wiring solutions that
factory workers and later owners had found, it is very common for
FSJs to light themselves on fire. A part of normal maintenance on
an FSJ should be to inspect the wiring and re-tape or splice out
bad sections of wiring. A long time owner that provides good
maintenance to their FSJ will likely replace the wiring harness one
wire at a time during the life of the vehicle.

Unfortunatly, there is currently no off the shelf wiring harness
available for Full-Size Jeeps. There are manufacturers of universal
style wiring harnesses that can be adapted into FSJs requiring a new

8.5.1 Painless Wiring

Painless Wiring makes universal wiring harnesses with 12 or 18 circuits.

Contact Painless Wiring

8.5.2 Centech

Centech makes several wiring harnesses.

Contact Centech

8.5.3 Ron Francis Wire Works

Ron Francis Wire Works makes custom harnesses for most applications.

Contact Ron Francis Wire Works

8.3 Rhino Chaser

The Rhino Chaser grille was available on Wagoneers from the start
of production until 1965; it remained on Gladiators until 1969.
Many have grafted this grille on to later models FSJs to give them
a tougher look. The Rhino Chaser grille covers only the radiator
opening with tall vertical slats.

8.4 Wide-Track Cherokees

The Wide-Track Cherokee became available in mid-1975. It is a 2-door Cherokee
that had 5″ wider flares than the Narrow Track Cherokee. It shares axles with
the J-10, which are a little wider than the Wagoneer and NT Cherokee. Between
the flares and wider axles it can fit a larger tire than a comparable NT.

To determine if a Cherokee is a WT, check the model number in the VIN. From
1974 through 1980 it is the 4th and 5th digit, from 1980 through 1983 it
is the 6th and 7th digit. A Wide Track is a model 17, the narrow track is
a model 16.

8.5 Body Lifts

Body lifts are possible for FSJs due to their body-on-frame
construction. Body lifts can help to make more room for larger tires,
but do not gain as much clearance as a suspension lift with larger tires.

For instance, if a 3-inch body lift is used to gain access for 31-inch tires over
the stock 29-inch tires, then the frame would gain about 1-inch of clearance due
to the increase in tire size. A 3-inch suspension lift with 31-inch tires would
gain 4-inches of frame clearance allowing for better break-over angles and moving
driveline components further out of harms way.

8.5.1 Performance Accessories

Performance Accessories makes body lifts for FSJs. The following are
listed on their web-site.

Description Year 2″ part# 3″ part#
J-10, J-20 pickup only 72-85 922 923
Cherokee 75-82 902 903

Contact Performance Accessories

8.5.2 Trailmaster

Trailmaster offers a 3″ Body Lift for 1975-83 FSJs.


420 Jay Street

Coldwater, MI 49036


Or find it at 4 Wheel Parts Wholesalers

8.6 Body Mounts

After years of neglect, many FSJs are in need of new body mounts and
other bushings. One may get lucky and find OEM-replacement mounts at
their local dealer or through specialty Jeep shops. Many also look
for polyurethane mounts.

8.6.1 ESPO Springs ‘n Things

ESPO provides polyurethane mounts for most FSJs.

Contact ESPO Springs ‘n Things

8.6.2 Daystar Products

Daystar Products also makes polyurethane mounts for FSJs.

Contact Daystar Products


9 Miscellaneous

9.1 Cost of Ownership

JEEP = Just Empty Every Pocket

9.2 Gas Mileage

A common question is “How can I make my gas mileage better?”

Answer: Sell your FSJ, buy a scooter.

Most V8 owners are lucky to top 13 MPG, a rare owner will have a
delicate right foot and a properly tuned vehicle and manage 15 MPG,
but this is very rare. More commonly, a FSJ built for off-road use
will average 8 to 10 MPG.

6-cylinder owners will generally do a little better, but rarely can
one break into the 20 MPG category. Many shoot for 18 MPG on


10 Acknowledgements

Thanks to all of the members of the FSJ mailing lists. Your
dedication and knowledge about FSJs has taught me many things in
the years I have owned my FSJ.

I would most especially like to call out Dennis “Doc” Fariello,
John Meister, Michael Baxter, and SuperKen. They have been on the
lists since the beginning, and have provided a wealth of
information to me.

I would also like to thank Joe Schaefer for his contributions, his
knowledge of these things is amazing. Please reference his awesome
FSJ Drive Train Database
for some more information about engines, transmissions, transfer cases,
and axles. It pulled together many loose ends and questions I had when
creating this FAQ.

Scott Probert (scotty), Todd Grisko (River Beast), porkchop,
and many others have provided a wealth of information on the IFSJA forum.




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