Adapting the

Chevrolet & GM Engines

to the

Jeep Tremec T176 & T177 Transmission

Jeep Adapter kit to GM Bellhousings

Kit G176, adapting the Jeep T176 transmission to GM bellhousings

This adapter assembly makes for a strong and convenient adaptation of classic standard shift GM bellhousings to the T176 four-speed transmission, as it was the premium transmission found in 1980-1986 CJ Jeeps.

Novak's G176 adapter is precision machined from aluminum alloy, and is designed to join GM bellhousings to the 1980-1986 Jeep CJ version T176. It is 5/8" thick, featuring an integrated bearing retainer. Included are the GM bellhousing locator / throwout sleeve, seal and hardware. The total adapted length of the T176 with this adapter is 13-5/8".

The adapter installs onto these transmissions with no change of input gear or other transmission internals. Cutting the transmission input shaft is not required as the adapter spaces the transmission properly for the GM crank and clutch assembly. Due to design constraints, the transmission's two top ears will require slight elongation with a round or rotary file. This process is simple and will not compromise the strength of the flange.

A new pilot bushing is required for this assembly. See Related Products below for the one matching your particular GM engine.

Applications & Compatibility

Compatible Transmissions

The T176 and T177 with ~6-3/4" stick-out input shafts from Jeep CJ's is compatible with this conversion. The similar T178 transmission from other Jeeps of this era feature longer input shafts and different gearing, and are not candidates for this conversion.

Compatible Engines

Nearly all GM Generation I-III engines are compatible with this conversion, including Chevrolet Small Blocks, Gen III+ V8's, Chevrolet V6's and Chevrolet I6 engines. Also, Buick, Olds, Pontiac, and other GM engines are compatible with this adapter assembly if you have a standard shift classic GM bellhousing and flywheel for your engine. Even some of the front wheel drive and unique engines could be made to work with this adapter using certain factory or aftermarket bellhousings sharing this common bellhousing / transmission bolt pattern.

GM Bellhousings

Chevrolet Muncie Saginaw Bellhousings

The classic Chevrolet bellhousing, with the four-bolt rear pattern. Buick, Olds, Pontiac and other bellhousings with the same rear face are equally compatible.

your GM bellhousings will typically feature either a 4-11/16" rear face bore or a 5-1/8" rear face bore, the latter typically only from Chevy / GM trucks from 1968-1991. Our adapter will works natively with the smaller bore bellhousing and with the larger bore bellhousing if you choose the 5-1/8" press-on spacer ring. If you are unsure of your bellhousing bore, buy the ring and return it after your build if it turns out you don't require it. See Related Products, below.

Clutch Assembly

Because of the 1-1/16" x 10 spline configuration of these transmissions, there is not a typical off-the-shelf clutch kit available for this swap. However, the installer can use a Jeep or Ford disc with the available pressure plate below.

Be aware of the following clutch configurations - see Related Products below for more information:

  • 153 tooth classic flywheels typically use a 10-1/2" clutch assembly
  • 168 tooth classic flywheels typically use a 11" or 12" clutch assembly
  • Gen III+ engines should use a taller aftermarket flywheel that normalizes the clutch kit to a classic 168 tooth style

The pilot bushing included with most clutch kits will not be compatible with the pilot tip diameter of these transmissions. See Related Products below to select your proper pilot bushing.

Clutch Release

The factory style bellcrank linkage system can be retained if the installer uses a GM release arm, #RAGM. This release arm is the best choice of release arm for either a GM engine swap in 1972-1986 CJ models, and some FSJ Jeeps - with the factory mechanical release system (not hydraulic). It's proper length gives the correct release action for GM clutches and is compatible with later rod & bellcrank linkage systems found in these Jeeps. See Related Items, below.

Some installers use this as a time to upgrade the factory's direct bellcrank style linkage with hydraulic release. Master cylinders from later CJ's and YJ Wranglers (the 1987-1990 version being most popular) can be installed on earlier CJ firewalls, and your GM bellhousing will accept one of Novak's popular #HCR Series slave cylinder kits, which include the release arm. For these and the appropriate hydraulic clutch line, see Related Products, below.

Clutch release bearings need to be a GM compatible unit. Because of the various heights of pressure plate fingers, consider Novak's adjustable throwout bearing assembly, available in Related Products, below.

For more theory and in-depth discussion about clutch systems, see Novak's Guide to Clutches, Linkages and Bellhousings.

Related Products


GM engine to T176 transmission pilot bushing
GM Gen III Engines to Jeep Pilot Bushing
Jeep to GM Clutch Release Arm
Adjustable clutch release throwout bearing
Hydraulic release master kit for Jeeps
Hydraulic release master kit for Jeeps
Adjustable clutch arm pivot
GM LS Vortec Bellhousing
GM Chevy Bellhousing
Extended depth flywheel for GM engines
Bolts for GM engine flywheel to crank
GM clutch kit
GM clutch kit
GM clutch kit
T176 Parts
1976-1986 Jeep floor tunnel cover

Engines & Engine Mounting

GM Engine Mounts for JeepsNovak engine mounts are available to ease the installation of your GM V6 or V8 engine. Novak has engines mounts for most Chevy, Buick and GM Gen III+ V8's.

Novak's engine mounts, feature vibration dampening, superior strength and useful adjustability - adjustable even after the engine is installed. The design, strength, and affordability of our mounts are second to none.

Engine placement in these Jeeps should consider the following points:

  • Left-right offset location is similar to factory at ~1-1/4" to the driver's side
  • Avoid installing the engine too low (axle clearance and other issues)
  • Avoid installing the engine too high (transmission tunnel interference, etc.)
  • Set your engine to 4-7 degrees of tilt rearwards, like the factory engine & powertrain
  • It is usually best that Chevy and Gen III+ V8 engines install approximately 3" further forward, using the back of the engine block face as the datum
  • When mocking up your engine installation location, pay special attention to radiator and fan clearance.
  • Firewall modifications are not expected.

Since Jeeps featuring the T176 transmission are "high-hood", clearance for classic Small Block and high Vortec (truck style) intakes and accessories is not a problem.

Novak Gen III+ engine mounts for 1976-1986 Jeep CJ models will remove any guesswork from the engine installation location as they are predetermined for the best location and engine clearance margins.

Driveshafts

Because many engines install about 3" further forward than factory, driveshaft length changes are often required, lengthening the rear and shortening the front by about that amount.

Some installers, concerned about the expense of new or modified driveshafts, attempt to let the existing driveshafts dictate engine, transmission and transfer case location, often to the detriment of the project. Our recommendation is to prioritize the correct position of drivetrain components over saving a few dollars which is usually regretted in the long run with compromised positioning.

Jeeps that require extensive travel or specialty-built driveshafts have this option available through several fabricators across the nation. These are normally specified after placement of the new transmission and measured at vehicle ride height. As the rear driveline gets shorter, it is often advantageous to us a Double Cardan or “CV style” rear shaft with the correct geometry at the axle to minimize vibrations and possible binding.

Axles

Use of factory axles is completely acceptable with this conversion. Axle upgrades are not necessary, but they may be chosen for reasons external to this transmission upgrade.

Also See