Transmissions
Manual Transmissions
T-90 Three Speed
The Borg-Warner T90 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 T90 with a column shift. The T90 had two knobs on the left side of the transmission. On T90's that had column shift this is where the shift linkages were mounted. Most T90's didn't have column shift but they still had these knobs.
The above image is a T90 with column shift. (This is JPet's T90) The column shift mechanism connects to the linkages on the side of the transmission.
The casing numbers on the T90 are T-90X-1X.
The T90 is 9 inches long.
There were 3 versions of the T90:
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.
T-86 Three Speed
The Borg Warner T86 was a three speed that came behind the Buick Dauntless V6 in 1966 and 1967. There was a factory adapter plate between the engine and transmission. The T86 is used in front of the version of Dana 18 transfer case that has the larger input hole. The T86 very similar to the T90.
The side of the T86 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 Three Speed
The Borg-Warner T14 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 Buick V6 but from 1973 to 1975 the T-14 could also be found with behind the strait sixes.
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 T14 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 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 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.
- Gear Ratios
- 1st – 3.00
- 2nd – 1.83
- 3rd – 1.0
- Reverse – 3.00
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
The casing numbers on the drivers side of the T150 are 2603983 or 2603347.
The input shaft is 7.5" long and 1 1/8" diameter with 10 splines.
The T150 is 9.25 inches long.
- Gear Ratios
- 1st – 2.99
- 2nd – 1.75
- 3rd – 1.0
- Reverse – 3.17
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 T18. The T-98 had lubrication problems and for that reason is not as desirable as the T18. 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 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.
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 T18 from the early '70s make sure to also get the bell-housing and adapter plate.
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 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 standardized. 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.
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 T18 or NP435 can be easily bolted to the bell housing in place of a T-176.
The T176 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.
- Gear ratios:
- 1st – 3.52
- 2nd – 2.27
- 3rd – 1.46
- 4th – 1.0
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 T18. 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 T18 is as long as a T5). 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.
SR4 Four Speed
This transmission was a light duty 4 speed transmission used in CJs in 1980 and 1981. In a CJ it was always married to the Dana 300 transfer case.
The top plate is held on with 11 bolts.
The SR4 transmission is 15.25 inches long.
The gearing of the SR4 depends on whether it is married to a 4 or a 6 cylinder.
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 150 (2.5L) four cylinder and the 258 strait six. Except for the missing overdrive this transmission is the same as a T5.
The T4 transmission is 15.25 inches long with 10 bolts holding on the top cover. It has an aluminum case with casing numbers 13-51.
- Gear ratios:
- 1st – 4.03
- 2nd – 2.37
- 3rd – 1.5
- 4th – 1.0
- Reverse – 3.76
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 T5 is a light duty transmission that always came with a Dana 300 transfer case. It is the same as a T4 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 T5. 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 T5. The strength of these transmissions is not as strong as originally hyped and it isn't recommended to rebuild your T5 into a World Class T5. A better option would be to replace the T5 with a stronger transmission such as the T176 or T18.
The T5 transmission is 15.25 inches long with 10 bolts holding on the top cover. It has an aluminum case with casing numbers 13-51.
- Gear ratios:
- 1st – 4.03
- 2nd – 2.37
- 3rd – 1.5
- 4th – 1.0
- 5th – 0.86
- Reverse – 3.76
Automatic CJ Transmissions
TH400 Three Speed Automatic
The GM Turbo Hydramatic 400 has the reputation of one of the best automatic transmissions ever made. This strong 3 speed automatic can easily handle a high horsepower engine. The only issue with the TH400 is it's relatively tall gearing. There are kits to lower the gearing but they are expensive. The TH400 is also a long transmission at 24.37 inches.
The TH400 was
the first automatic transmission to come in a CJ. It was available from
1976 to 1979. It only came in CJs that were equipped with the QuadraTrac 1339.
- Gear Ratios
- 1st – 2.48
- 2nd – 1.48
- 3rd – 1.00
- Reverse – 2.07
TF999 Three Speed Automatic
The Torque Flight 999 is a Chrysler medium duty three speed. It was uncommon but used in CJs from
1980 to 1986. The TF999 was only used in front of the Dana 300 transfer case and it
only came behind the 258 strait six.
The TF999 is 22.5 inches long.
- Gear Ratios
- 1st – 2.74
- 2nd – 1.55
- 3rd – 1.00
- Reverse – 2.20
TF904 Three Speed Automatic
The Chrysler Torque Flite 904 is a light duty three speed transmission that was
only offered with the four cylinder engine. If you ordered a strait six you would get the TF999 transmission. The TF904 was offered in CJ's from
1980 to 1986. From 1980 to 1983 the TF904 had a Chevy bolt pattern because it was bolted to the “Iron Duke” engine. From 1984 to 1986 the bolt pattern changed to accommodate the AMC 2.5L engine.
The TF904 was always married to the Dana 300 transfer case.
- Gear Ratios
- 1st – 2.45
- 2nd – 1.45
- 3rd – 1.00
TF909 Three Speed Automatic
The Chrysler Torque Flite 909 is the basically the same transmission as the TF904. The only difference is the TF909 comes with a lock-up torque converter.
- Gear Ratios
- 1st – 2.45
- 2nd – 1.45
- 3rd – 1.00
