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The Novak Guide to the
Borg-Warner T14 Transmission

The Jeep T14 Transmission

The Borg-Warner T14 is a lighter-duty, three-speed transmission, introduced in the 1967 CJ5 and C101, and was offered in Jeeps up through 1975. The T14 was found only behind the Buick V6 engine until 1972, when it was provided as the base transmission for the AMC 232 and 258 I6 engines.

Features
The T14 is a top loaded, top shifting transmission using a cane shift lever.

The T14 is fully synchronized in all forward gears and all gears are helically cut. It uses sliding clutch collars in lieu of sliding gears as found in other, earlier Borg Warner three speeds.

Identification
The T14 transmission is 8-11/16" long and features a cast iron top cover that is retained by six bolts. The main case is of cast iron. The case itself has two protruding bosses as provisions for side-shifting actuators, however, no known Jeep side-shift applications are known.

All T14 transmissions have a 1-3/16" x 10 spline output shaft for mounting the transfer case input gear (or overdrive barrel gear). The T14 was the only Jeep transmission to feature this distinctive spline configuration.

The T14 may have the following casting numbers: T14, T14AA or 1302 and these are typically found on the passenger's side.

T14 Transmission Specifications

Jeeps also had a T86 transmission available with the Buick V6 from 1966-1969. It was similar in form and appearance, but its casting numbers will differentiate it from the T14

There are two versions of the T14 to note, depending on its year and mating engine. All early Buick V6 T14's used a different input shaft/gear than the later AMC 232 & 258 T14's.

The T14 and T15 are similar in designation, and visually somewhat similar. However, the T14 did use a three-bolt front bearing retainer whereas the T15 used a four-bolt front bearing retainer.

Transfer Case Compatability
The Jeep T14 was factory-married to the Jeep Dana Spicer Model 18 transfer case, and only the large (4") input bore versions.

T14 was available attached to the Jeep Dana Spicer Model 20 transfer case in the 1972-1975 Jeeps.

The T14 always used a 10-spline transfer case input gear. An informative chart of these gears can be found here. Care should be taken when ordering adapters for transmissions replacing these 10-spline gearboxes.

Engine Compatibility and Adaptability
The earlier T14 had a 1-1/8" x 10 spline input shaft (or "clutch shaft") and its pilot tip is ~19/32" in diameter. Later AMC era T14's had the same spline configuration, but the pilot tip increased in size to ~3/4" in diameter.

GM
The T14 used a standard Buick bellhousing from 1967-1970. It used a factory bellhousing adapter in cast iron during these years and a special input bearing retainer. It is also possible to adapt the T14 to a variety of GM bellhousings with our T14 adapter assembly.

While it is mechanically possible to marry many GM bellhousings to this adapter, stronger upgrade engines can be overwhelming to the T14, as it is a lighter-duty gearbox.

In 1971, AMC cast a special Buick bellhousing that was deeper, and machined to match the T14's native front bolt pattern. This unique bellhousing also used a special cable clutch release.

AMC 232 & 258
The 1972-1975 Jeeps with the AMC I6 had its own, dedicated bellhousing to the T14. This was a deeper bellhousing (~9") than the standard AMC bellhousings that would be released in 1976.

When filling your T14 with gear oil, we recommend that you select a conventional mineral oil or a para-synthetic in lieu of a full synthetic oil. Properly assembled manual gearboxes do not have the thermal strains seen by combustion engines or hypoid gears. Synthetic fluid in these gearboxes, while not harmful, is probably an economic waste.

Hypoid gear oil is sulphurized higher than transmission oil and can be mildly corrosive to the non-ferrous alloys used for synchros, bushings and thrust washers in these transmissions.

An 80W-90, API-GL5 or MT-1 rated fluid is very good. Some claim faster shifts from using a 50W engine oil in their transmission and we do not consider this to be contraindicated unless you operate your vehicle in a very warm environment.

Rebuilding the T14
The T14 is quite easy and enjoyable to rebuild. Many shadetree mechanics do very outstanding rebuilds if they have access to a press, snap ring pliers and bearing pullers.

We welcome you to contact us for T14 master rebuild kits and components.

Summary
The T14 offered decent service in lighter Jeeps. The T14 was replaced in Jeeps by the T150 transmission in 1976.

Sources
- The Novak archives and our customer's input
- Jeep Technical Service Manuals
- Jeeptech.com & Terry Howe