CJ-7 Projects


Lightforce Lights - H.I.D. High-intensity discharge Upgrade

HEI Ignition System (GM Style) Installed in the AMC 360 V8
Getting rid of gremlins and improving performance

Installing 23,000 Volt Offroad Lights

Autogage Tachometer Installation

 Home Page
 Photo Album
 Product Reviews
 Cool Products
 Tech Section
 Readers Rigs
 4x4 Club Links
 Links Directory
 Shop Offroaders
 Centralia PA
Project CJ-7
Offroaders Guide
to Gearing up
for Offroad

From Basic Equipment to Well Equipped.  An extensive list guide to help you prepare your vehicle for the offroad.


Onboard Air
Converting a York
AC Compressor
to Pump Air

Trailering Safety and Trailer Hitch Information


Off-Road Truck Driving Techniques and Safety

Off-Road Lights
by LightForce Product Review / Installation.
from Off-Road Lights


Jeep Dana 300 TeraLow - 4:1 Gearset for the Dana 300 Transfer Case

AMC V8 Engines
GEN-1 Nash/Hudson/Rambler V-8s (1956-1966) through to the GEN-3 AMC Tall-deck (1970-1991)

Chevy Small-Block V8 Engines
Chevy Small-Block V8 Engines Manufactured by General Motors - Production: 1955?2002

Hemi Engine - All about the Hemi Engine

Ford Engines
4 Cylinder, 6 Cylinder, 8 Cylinder, 10 Cylinder, 12 Cylinder Ford Engines

Ford V8 Engines
8 Cylinder Engines manufactured by Ford

Ford 351 Cleveland V8 Engines
351 cubic inch V8 Engines manufactured by Ford

Chrysler Hemi Engine

AMC V8 hp/Torque, Compression & Bore/Stroke by year

Engine Size Conversion Table
Converting engine displacement from CID, Liters, C.C.

Engine Overheating Basics - 16 Common Causes of an Overheated Engine

Fan Clutch Diagnosis
How to tell if the Fan Clutch in your Cooling System is failing or has failed.

Automotive Gauges & Instrument Functions
Information they display & their importance.


From the
Department of Cheap   Tricks and Useful Tips

Ultra-Cool Hand Throttle for Free!

Jeep V8 Swap Tips

The Exploding Clutch

Radiator Protection using 6 bucks worth of material

Cracked Under Pressure - Fixing a smashed fingernail

A Cheap, effective alternative to undercoating

Home-built Saginaw Gearbox Brace for the cost of lunch!

Ammo Box Storage - Mounting Them for Quick Disconnect

Home-built Serious Skid-Plate protection for the Oil Pan for under 20 bucks!

Ramp Travel Index
RTI / Ramp Travel Index  What it is and how to calculate it, with and without the ramp.





Project Jeep CJ-7   
The Transmission
T-18A Rebuild &
Short Shaft Conversion

Back to Project Index


shafted.jpg (9365 bytes)

Dcp_1558.jpg (18424 bytes)Originally the T-18A manual transmission came out of a J-20 Pickup and the T-18A's input shaft ran though a 5 inch adapter before emerging into the bell housing.  This T-18A's new life will be lived out in a CJ-7 which has a shorter wheelbase when compared to the J-20.  To properly fit the transmission into the CJ-7 the 5 inch adapter would need to be removed. After removing the adapter it becomes necessary reduce the length of the input shaft. Hicks 4x4 Specialists in California sells a short shaft kit for the T-18A. Through OK 4 Wheel Drive, who I preferred to deal with, a kit was ordered from Hicks and OK was able to match the price Hicks gave me for the kit.  Swapping the input shaft require that the transmission be disassembled so this is a perfect opportunity to rebuild the T-18A to ensure good reliable service for many years to come.  The kit was also ordered through OK 4Wheel Drive.

The Short Shaft Kit comes with three items.  The Shaft, the shaft housing and a pilot bearing.

The T-18A rebuild kit comes with 2 main bearings, new needle bearings, new spacers, new snap rings, new synchronizers, new Teflon guides and new gaskets for all the openings.

Mike from www.JeepFan.com who has the same transmission and had gone though the same process of rebuilding his T-18A and swapping the input shaft offered to help with the rebuild.  This was much appreciated since he remembered all the little quarks and issues he had to deal with as well as avoiding some of the mistakes he encountered while doing his own.

shafted.jpg (9365 bytes)

Input Shaft comparison.

Preparation for the Saturday afternoon job included taking inventory of the parts we would need, getting tools together and also adding a sheet of 16 gauge galvanized steel to the top of the work bench.  The sheet metal is a great addition to the work bench.

Dcp_1571.jpg (10272 bytes)Some of the tools we needed to have on hand above and beyond the standard set of sockets and wrenched were a soft mallet (copper), snap ring expanders, a 1 inch dowel about 12 inches long, a Haynes manual for the CJ which had a blowup of the T-18A that proved to be handy, petroleum jelly for the needle bearings, ziplock bags for marking bolts and parts as it was disassembled, gasket sealer, carb cleaner, Simple Green Degreaser and a camera.  One thing I can say is don't hesitate to take notes.  I know it's great to just dive in and ripe it apart but remembering how it came apart and what snap ring goes where makes the job go much easier.  Also bag and mark old parts.   Doing this helped keep track of what went where and made it easy to find bolts and parts when it was time to reassemble.  Taking pictures is a good idea too.   Having a digital camera was nice because if needed I could review an image taken earlier for whatever reason.  

Mike remembered much of the process and was very helpful but if this job would have been done by myself alone or with someone who has not rebuild a manual trans before, the notes taking and pictures would have been very useful.   I recommend having a second set of hands.  In some cases such as extracting the upper gear set from the case, having two people handling this large and heavy gear set was almost a necessity. Also having a manual to reference and a blow-up image of a T-18 was also very useful for understanding how it came apart and even more important, how it goes back together.  For your reference the image to the right links to a printable image contained in a Word document of a T-18 exploded view illustration.

Word Document

JPG Image only

broom-stick.jpg (7439 bytes)

1 inch dowel is needed for replacement of the needle bearings.   Pictured on the dowel is the tubular spacer between the 4 sets on needle bearings.   On either end is a washer that spaces out the sets of needle bearings.

Dcp_1545.jpg (10694 bytes)

Dcp_1544.jpg (19939 bytes)

Above is the stock input shaft of the T-18A that came out of the J-20.  This needs replacement because of the removal of the 5" adapter between the T-18A and the Bell housing.  Hicks 4x4 provided a Short Shaft Kit.


Dcp_1546.jpg (12577 bytes)

We kick off the project by removing the top of the T-18A exposing all the guts of the beast.  Removal of the stick shift is not necessary.  Behind the workbench was a table where we could layout all the pieces.

Dcp_1547.jpg (9769 bytes)

Dcp_1549.jpg (13915 bytes)


Next we removed the rear shaft bolt and the output gears.


Dcp_1550.jpg (10890 bytes)

Next we removed the front snap ring and the front bearing using a break tool.


This is one area where two people come in handy.  Removing the gear sets.  We removed both at the same time pulling them in opposite directions while lifting them where they join together. Roller bearings from between both gear sets dropped all over. 


This exposed the lower gears.

Dcp_1551.jpg (9818 bytes)

Dcp_1552.jpg (10822 bytes)


Dcp_1553.jpg (14382 bytes)Lower gears were removed by sliding the rectangular plate up out of the slots in the shafts and then driving the shafts out using a 1 inch dowel rod or a brass drift.  The larger Countershaft is driven forward.  The small reverse idler shaft shaft will clear internal parts when driven inward however it is possible that the small shaft is tapered on some models at the rear of the transmission and should be driven out (rearward) from the inside.  We drove it inward towards the front without any issues but to be safe, you should drive it rearward.
Note: The T98 and the T90 are similar in design to the T18 but they have a tapered reverse idler shaft and must be drive out from the inside or you'll damage the case.


Rear set of gears were disassembled to get to synchronizers.  Don't forget how it came apart.  Also be aware of some spring loaded bearings that lock the gear set in place during shifting. 

Everything was then cleaned using a combination of carburetor cleaner and Simple Green in a basin of hot water.

Dcp_1555.jpg (14621 bytes)

Dcp_1554.jpg (16134 bytes)

Dcp_1561.jpg (9899 bytes)


Dcp_1557.jpg (14433 bytes)

Dcp_1560.jpg (8718 bytes)

Cleaning and inspecting the parts.  Everything looked pretty good.   Gears were in good shape with very few chips in the leading edge of the 1st gear.


Dcp_1562.jpg (10779 bytes)Next we packed needle bearings into lower shaft. Used petroleum jelly to hold it all together.  The petroleum jelly will disintegrate once exposed to the gear oil.  This is where the one inch dowel rod comes into play. Each bearings set gets 22 bearings. The bearings go in in specific order with the tub in the center of it all. Moving outward from the tub each side (front/rear) gets a ring, 22 bearings, a rings, 22 bearings and a final ring.


Dcp_1563.jpg (12746 bytes)

This is the tricky part.   We then lowered the gears into case while holding shims and washers at each end.   Refer to your manual for which shims and washers go where.  I used a short piece of the 1 inch dowel to help hold the washers in place while lowering the gear set.   It took a few trys but we got it lined up right. Next we tapped the lower shaft into place pushing dowel rod out while keeping pressure on dowel to prevent it from bouncing out to fast.

Next we packed the input shaft with needle bearings using petroleum jelly again to hold them in place.  No dowel with this set of bearings.  Then we lowered both of the upper gear sets into case with the front and rear going though the case openings and gently lowering the center putting them together.  Remember those needle bearings will move easily so be careful. Once together we put new main bearings in the front and rear of the case. Take Dcp_1564.jpg (12646 bytes)note of width of bearings. Larger width in rear, narrow in front.  I had been informed that some people were getting the two main bearing and they were the same size when there should have been different sizes for front and rear.  Those people had to re-order a bearing or reuse the old one that wasn't included.  I had the right sizes.  Gentle tap bearings onto shafts. Use a pipe or gentle tap on inner part of bearing with a wooden block and a hammer. Alternate sides if using a block.


Dcp_1565.jpg (9319 bytes)

The Front bearing needs to be in right place (close to the snap ring on the shaft) or shaft cover will bind the bearing.  I discovered this when I went to bolt on the shaft cover for a test fit.   I had to tap shaft in using a piece of aluminum sheet metal to cover the end of the shaft and hit it with a hammer. I then greased the seal that's part of the shaft cover, applied gasket sealer, gasket, more gasket sealer and put shaft cover on with port side down. Not too much sealer around port as not to clog the port but enough to seal it.

Dcp_1574.jpg (10721 bytes)


Dcp_1569.jpg (21547 bytes)

The top half was then cleaned and the casket and gasket sealer was removed using a wire wheel on a drill to brush off the silicone sealant.

Dcp_1568.jpg (14093 bytes)


Dcp_1570.jpg (21336 bytes)
T-18A to Dana 20 Adapter

I had to get a new rear seal.

I removed the seal with WD-40 can and cleaned the adapter. I couldn't find a gasket that is to go between the T-18A and the adapter so I made a gasket.

Dcp_1577.jpg (11667 bytes)

Dcp_1581.jpg (7501 bytes) Dcp_1583.jpg (6556 bytes) Dcp_1584.jpg (8199 bytes)


I then put the new seal in using the old bearing from teh T-18A which fit perfectly over the seal. The main thing is to push on outer rim of seal only as not to damage the seal. I then cleaned the adapter again, applied gasket sealer, the gasket, more sealer and bolted it on. Cleaning the bolts too helps to seal it better.
Dcp_1585.jpg (3403 bytes) Dcp_1586.jpg (8040 bytes)


PTO plate was remove later, cleaned painted and attached with new gasket. Dcp_1594.jpg (6685 bytes)

Clean top half, remove old Teflon guides and replace with new from kit.

Dcp_1595.jpg (9863 bytes)   Dcp_1596.jpg (7172 bytes)

Before filling with gear oil and sealing it up I did a test fit of the top for proper alignment of gears. I put a few bolts in to test run gears. Everything worked well and I removed the top without moving the gear position.  It was then filled with an 80W 90 GL-5 gear oil to to fill bolt (maybe a little more). The seal area was cleaned again and on went the sealer, gasket, sealer and the top. A final run though the gears again before a torque down of all the bolts.

Dcp_1579.jpg (16096 bytes) Dcp_1580.jpg (7766 bytes)

Test fit of the cleaned and
painted V8 bell housing.



Project Jeep CJ-7 ~ The Transmission

Back to Project Index




Offroad Tire Info
Tire Terminology
Wheel Terminology
How to Pick the Right
Tires for your Truck
Truck Tire Info
Tires - What Hits What Fits
All Terrain  Mud Terrain
Tire Reviews & Info
Mud Terrain MT Tire Reviews
All Terrain AT Tire Reviews
Super Swamper Bogger
Super Swamper SSR
Super Swamper SX
Super Swamper Vortrac
Interco IROK TSL
Super Swamper LTB
Super Swamper TSL
Super Swamper TSL Radial
Super Swamper Narrow
Interco SS-M16 Swamper
Thornbird TSl Radial
Thornbird TSl Bias
Thornbird TSL
Parnelli Jone Dirt Grip
BFGoodrich Krawler
BFGoodrich MT T/A KM
BFGoodrich MT T/A KM2
BFGoodrich AT TA KO
BFGoodrich Mud King XT
Bridgestone Dueler MT
Cooper Discoverer ST
Cooper Discoverer STT
Cooper Discoverer ST/C
Firestone Destination MT
General Grabber MT
General Grabber AT2
Green Diamond Icelander
Ground Hawg Mud Tire
Hankook Dynapro MT
Hankook Dynamic MT RT01
Hercules Terra Trac MT
Hercules Trail Digger MT
Kelly-Springfield Safari DTR
Kelly-Springfield Safari MSR
Kumho Road Venture MT
Kumho Road Venture KL71
Kumho Road Venture AT
Dick Cepek Mud Country
Dick Cepek F-C II
Dick Cepek Fun Country II
Dick Cepek Fun Country Nylon
Dick Cepek Fun Country Kevlar
Mastercraft Courser MT
Mastercraft Courser HTR
Mastercraft Courser HTR Plus
Maxxis BigHorn Radial
Maxxis Creepy Crawler
Maxxis Trepador
Maxxis Buckshot Mudder
Maxxis MA-SW
Maxxis M-8080 Mudzilla
Maxxis MT-754 Buckshot
Maxxis MT-753 Bravo
Maxxis MA-751 Bravo
Maxxis MA-S2 Marauder II
Maxxis MA-S1 Marauder
Maxxis MT-762 BigHorn
Nitto Mud Grappler
Nitto Dune Grappler
Nokian Vatiiva MT
Pit Bull Rocker Extreme
Pit Bull Maddog
Pit Bull Growler
Goodyear Wrangler MT/R
Pro Comp Xterrain
Pro Comp All Terrain
Pro Comp Mud Terrain
Pro Comp Xtreme AT
Pro Comp Xtreme MT
Toyo Open Country MT
TrXus Mud Terrain
TrXus STS All Terrain
Mickey Thompson MTZ
Mickey Thompson MTX
Mickey Thompson Baja Claw
Mickey Thompson Baja Crusher
Competition Claw
Dunlop Mud Rover
Yokohama Geolandar

Latest trips Offroad
... trail reports with the Project CJ-7
click here.

Sounds System, Raised the Rear Seat
Storage below and a great place to mount 6x9 Speakers for Great Bass ... In a Jeep!

York AC Compressor Conversion.  What used to pump Freon, now pumps compressed air to the front and rear bumpers.  125 psi,  2 gallons of storage, air fittings at the bumpers, enough CFM to power air tools!.  Click Here for more  Details


Dick Cepek's 2008 F-250 Super Duty Project Vehicle ? Project CRUSHER

Warn X8000i
Winch Installation

ARB Air Locker Install
Jeep Wide Track Axles Swap

Mud Tire Reviews

Building a Garage?
Need a Garage Plan?

Reader's Rigs and Seriously Stucks!


Jeep Trans Swap Info
T-18A Transmission Rebuild & Short Shaft Conversion