Manual CJ Transmissions

Manual CJ Transmissions

BusaDave9

Always Off-Roading Jeeper
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Durango, Crawlarado
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1979 Jeep CJ5 with 304 V8, T18 Transmission, Dana 20 Transfer case with TeraLow 3:1 gears, 4.88 axle gears, Detroit Locker up front and Ox Locker in back with 1 piece axle shafts, 36" SuperSwamper SX Tires, Shackle reversal, MileMarker Hydraulic winch, MSD 6A ignition.
T-90
Three Speed


auctivacommerce-com-t90.jpg
The Borg-Warner T-90 was a strong three speed Transmission that was used in CJs from 1945 to 1971. All the CJ2a 's in 1945 and some in 1946 had a T-90 with a column shift. The T-90 had two knobs on the left side of the Transmission . On T-90 's that had column shift this is where the shift linkages were mounted. Most T-90 's didn't have column shift but they still had these knobs.
_467477.jpg


_467477.jpg

The above image is a T-90 with column shift. (This is JPet's T-90 ) The column shift mechanism connects to the linkages on the side of the Transmission .

The casing numbers on the T-90 are T-90X-1X.
The T-90 is 9 inches long.

There were 3 versions of the T-90 :
The T90A1 was used from 1946 to 1962 behind the four cylinder engines.
The T90C was used from 1963 to 1971 behind the F-Head four cylinder engines.
The T90J was used from 1952 to 1965 in six cylinder trucks.

t90.jpg

Information for this post was obtained from Novak Jeep Conversions

t90_ratios.jpg
 
T-86

T-86
Three Speed

The Borg Warner T-86 was a three speed that came behind the Buick Dauntless Buick 225 V6 V6 in 1966 and 1967. There was a factory adapter plate between the engine and Transmission . The T-86 is used in front of the version of Dana 18 Transfer Case that has the larger input hole. The T-86 very similar to the T-90 .

The side of the T-86 is stamped “T86AA” or "T86X-1X"

The T-86 was also used quite often in Studebakers.

Gear Ratios
1st – 2.79
2nd – 1.68
3rd – 1.00
Reverse – 3.79
 
T-14

T-14
Three Speed

The Borg-Warner T-14 was a cast iron three speed Transmission that was used in CJs from 1967 to 1975. It was not a very strong three speed. Most T-14 's were paired up with the Dauntless Buick 225 V6 but from 1973 to 1975 the T-14 could also be found with behind the strait sixes.


69cj5inwi_t14.jpg

The T-14 's also had the knobs on the left side, similar to the T-90 . These knobs would go unused on CJ's since they were used for column shift linkages and the T-14 never used a column shift when installed in CJs.

The T-14 Transmission is 9 11/16 inches long.

The T-14 is similar to the T-15 . The casing is the same but the front bearing retainer is held on with 3 bolts whereas the T-15 uses 4 bolts.

Gear Ratios
1st – 3.1
2nd – 2.61
3rd – 1.0
Reverse – 3.1
 
T-15

T-15
Three Speed

The T-15 is a heavy duty three speed Transmission that was available in CJ's from 1972 to 1975. For the most part it was mainly offered with the AMC 304 V8 but in some cases it was found behind the strait sixes if the buyer were to specify the heavy duty three speed. The T-15 is the strongest three speed ever offered in a CJ.
The T-15 is ten inches long.

t_15_with_dana_americanlisted.jpg

Image from americanlisted.com



Gear Ratios
1st – 3.00
2nd – 1.83
3rd – 1.0
Reverse – 3.00
 
T-150

T-150
Three Speed

The Tremec T-150 is a stout cast iron three speed that was available in CJ's from 1976 to 1979. It was always mated to the Dana 20 Transfer Case . The front of the T-150 has a “butterfly” bolt pattern that is the same as what is found on Fords. For that reason a Ford V8 can be placed in front of a T-150 without too much work. As long as the V8 is not built up for high horsepower the T-150 should be able to handle the power. To do this swap the tip of the input shaft needs 5/8 inch cut off. For more details check out Novak's web site: Installing Ford V8 Engines into the Jeep CJ, 1976-1979

t150_transmissionnovak.jpg

The above image if from Novak's web site novak-adapt.com



The casing numbers on the drivers side of the T-150 are 2603983 or 2603347.
The input shaft is 7.5" long and 1 1/8" diameter with 10 splines.
The T-150 is 9.25 inches long.

Gear Ratios
1st – 2.99
2nd – 1.75
3rd – 1.0
Reverse – 3.17




t150-alumitub78-greatlakes4x4com.jpg

alumitub78's T-150 Transmission from greatlakes4x4com

 
T-98

T-98
Four Speed

The Borg-Warner T-98 was a heavy duty 4 speed granny low Transmission used in CJ's from 1955 to 1970. It was the predecessor to the T-18 . The T-98 had lubrication problems and for that reason is not as desirable as the T-18 . There are no adapters to mount it on the back of the AMC engines.

Gear ratios:
1st – 6.4
2nd – 3.09
3rd – 1.69
4th – 1.0
 
T-18

T-18
Four Speed

The Borg-Warner T-18 was the best factory installed Transmission to ever go into a Jeep. This is a truck Transmission and it shifts as such. This heavy duty Transmission was available in CJs from 1971 to 1979. According to the guys at Novak Jeep released 12 different versions of the T-18 . Most variations were different gearing and input shaft lengths. The most desirable T-18 's had the granny low first. These were referred to as the T-18a. All the T-18 's in CJ's from 1977 to 1979 had this T-18a wide ratio gearing. From 1972 to 1975 most T-18 's in CJ's had close ratio gearing. These transmissions also had an adapter plate between the Transmission and the bell-housing.
ford_t18.jpg
The above T-18 is out of a Jeep. Ford T-18 's have the PTO on the passenger side.


Transmission swaps – Since this such a desirable Transmission for off-road use it is a common swap into CJ's. Unfortunately Jeep used many variations of this Transmission . If you would like to install a T-18 into your CJ the first thing to consider is what Transfer Case you have. If you have a Dana 20 Transfer Case (1970's) then you are best off looking for a T-18 (or T-18a) out of a CJ. It is an easy swap but expect to have the drive shaft lengths modified.
If you find a T-18 from the early '70s make sure to also get the bell-housing and adapter plate.

t18-fsj-adapter.jpg
The above T-18 is from a full sized jeep. It has a long input shaft and a factory adapter behind the bell-housing. To install this T-18 in a CJ you will have to remove the adapter and install a shorter input shaft.

ford_t18.jpg

Ford T-18 with an adapter to mate it to a Dana 300
If you have a Dana 300 Transfer Case (1980's) you are better off getting a Ford T-18 and an adapter to mate it to your Transfer Case . Both Novak and Advance Adapters sell such an adapter kit. This entails replacing the main (output) shaft of the T-18 . This is the best route because the T-18 with adapter is as long as the T-4 and T-5 transmissions. For that reason this swap can be done without modifying the drive shaft lengths. This swap also entails drilling and tapping 4 holes in the bell-housing. The reason I don't recommend a Jeep T-18 to mate to the Dana 300 is because the Ford 18 was standardised. You know what you are getting. You could get an adapter to mount a Jeep T-18 to a Dana 300 but you will have to modify the lengths of both drive shafts.

t18_ratios.jpg


info for this post was obtained from novak-adapt.com
 
T-176

T-176
Four Speed

The Tremec T-176 was one of the better transmissions of the '80s. It had an aluminum case and was used in CJ's from 1981 to 1986 (mostly for export.) It is a four speed that was always mated to the Dana 300 Transfer Case .
The front of the T-176 has a ford “butterfly” bolt pattern similar to the T-150 . For that reason a Ford T-18 or NP435 can be easily bolted to the bell housing in place of a T-176 .

The T-176 Transmission is 12.9 inches long if you include the factory adapter that is used to bolt it up to the Dana 300 Transfer Case .

t176.jpg
Gear ratios:

1st – 3.52

2nd – 2.27

3rd – 1.46

4th – 1.0
 
Weak transmissions of the 1980's

Weak transmissions of the 1980's
SR4 , T-4 and T-5

Jeep CJ's of the eighties were plagued by some of the worst transmissions ever to go into CJs. The SR4 , T-4 and T-5 were all light duty transmissions. They were all made by Borg-Warner and since they were based on the same design there are a few things that can be said of the group. They all used the same aluminum case with the shift lever in the tail-housing. These transmissions are hard to tell apart because the casings are the same. The easiest way to tell them apart is by the year of the Jeep and the number of forward gears.

Since the tail-housing also includes the shift lever it is not easy to swap a 2WD Transmission into a CJ. To swap the shift mechanism is too much work to make it worth while. As a matter of fact these three transmissions have such a poor track record that Novak and Advance Adapters do not have any adapters to help installing these transmissions. Don't get me wrong, there are a lot of CJs that are still driving around with these transmissions without a rebuild but when it comes time to do a swap you don't want to spend much time or money trying to keep any one of these three transmissions.

What Novak and Advance Adapters do have is adapters to get rid of these three transmissions. Luckily these three transmissions have a common bell-housing bolt pattern that makes it easy to swap out in favor of an SM420 or SM465.
All three of these transmissions have an input shaft that is 7-1/2 inches long.
I have once swapped out a T-5 Transmission in favor of a T-18 . When doing this swap it's easiest to get a Ford T-18 and a kit from Advance Adapters or Novak. To do this swap you have to replace the output shaft of the T-18 . The adapter is the correct length to avoid having to change the drive lengths (the adapter and T-18 is as long as a T-5 ). The Ford T-18 will mate up to the Jeep bell-housing but you will have to drill and tap 4 holes. The Ford input shaft is the correct length.

All three of these transmissions (SR4 , T-4 and T-5 ) have the same bell-housing bolt pattern.
 
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T-4

T-4
Four Speed
The Borg-Warner T-4 was a light duty Transmission that was offered in CJ's from 1982 to 1986. It came behind the AMC 150 (2.5L) four cylinder and the AMC 258 i6 / 4.2l strait six. Except for the missing Overdrive this Transmission is the same as a T-5 .

The T-4 Transmission is 15.25 inches long with 10 bolts holding on the top cover. It has an aluminum case with casing numbers 13-51.
t4_novak.jpg

Image from novak-adapt.com


For more information see the above post (Link)-> Manual CJ Transmissions -<

Gear ratios:
1st – 4.03
2nd – 2.37
3rd – 1.5
4th – 1.0
Reverse – 3.76
 
T-5

T-5
Five Speed
From 1982 to 1986 the Borg-Warner T-5 was offered in CJ's as as Overdrive Transmission . As a matter of fact this was the only Overdrive Transmission offered in a CJ. The T-5 is a light duty Transmission that always came with a Dana 300 Transfer Case . It is the same as a T-4 except it has an Overdrive .
There was a heavier duty T-5 Transmission that was used in street vehicles such as Mustangs. These transmissions were referred to as World Class T-5 . They were never offered in Jeeps or any other four-wheel drive but there are companies such as Astro Performance that offer the gears and parts to rebuild the T-5 into a World Class T-5 . The strength of these transmissions is not as strong as originally hyped and it isn't recommended to rebuild your T-5 into a World Class T-5 . A better option would be to replace the T-5 with a stronger Transmission such as the T-176 or T-18 .

The T-5 Transmission is 15.25 inches long with 10 bolts holding on the top cover. It has an aluminum case with casing numbers 13-51.
t5-5speeds-com.jpg
Image from 5speeds.com



For more information see the above post (Link)-> Manual CJ Transmissions -<
Gear ratios:
1st – 4.03
2nd – 2.37
3rd – 1.5
4th – 1.0
5th – 0.86
Reverse – 3.76
 

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