Our T18 to the Jeep New Process (or New Venture Gear) transfer cases conversion makes for a strong and capable assembly both on-road and off-road, and it remains one of our preferred manual transmission to transfer case combinations.
The Novak T18 / T19 to Jeep New Process transfer case adapter is very compact at only 3.2" long for a combined transmission and adapter length of 15.2". The adapter itself is cast and precision-machined of aluminum alloy, featuring thick flanges, a heavy cross-section, and strength-adding gussets. The adapter itself is cast and machined of 356-T6 aluminum heat treated alloy, featuring thick flanges, a heavy cross-section, and strength-adding gussets. It is drilled for over 20 degrees of transfer case clocking locations, though the provided factory angle will suffice for most New Process transfer cases.
This transfer case adapter's design features a modular mounting and support system and mounting base, ready to accept our industry standard urethane isolator mount, available in Related Products, below.
The new Novak manufactured 23 spline output shaft is machined from premium alloy steel and hardened for maximum strength and longevity ready to be installed in your Borg-Warner transmission and then spline directly into your 23 spline transfer case - a 21 spline version is not available. Details below.
The adapter kit is designed for compatibility with 23 spline Jeep NP207, NP231, NP242, NP249, NP241 & NP241OR "RockTrac" transfer cases. Below is a summary of spline counts and lengths usually encountered.
A more detailed discussion of New Process input gears is found here.
The 21 spline shaft is substantially weaker than the 23 spline version. 21 spline versions were only used in the 4 cylinder applications and some very early automatic 6-cylinder versions. Novak does not make a 21 spline version of this adapter kit because of this weakness, vs. the exceptional torque created by the compound low gear of this transmission.
Our recommendation is to change the transfer case input gear to a 23 spline version. See Related Products, below.
Any Ford, Jeep, IH - 2wd or 4wd (either works equally well) versions and year of the Borg Warner can be adapted to these transfer cases.
Mainshaft replacement is largely straightforward. Good work is within easy reach of the careful home mechanic and instructions are included. We also recommend our basic gasket & seal kit, or this is a good time for a more thorough master rebuild and update of the transmission.
Some installers consider one of our complete Novak remanufactured and upgraded transmission packages. This is a professionally built and dyno-tested transmission, delivered ready to bolt into your Jeep build.
This kit is compatible with any Jeeps in which the Dana 300 was available, and most thereafter. This is one of our shortest 4-speed combinations and they fit nicely into the tunnel of most Jeeps.
Any engine that can be made to work with the T18 or T19 will work with this conversion. They include:
Ford and AMC engines are the two most natural and recommended choices for this transmission.
The transmission shaft installation takes more specialized tools, heavy snap ring pliers, a press to remove and replace bearings, etc. Normal mechanics tools are required for the balance of the installation.
Engine placement in these Jeeps should consider the following points:
Since Jeeps featuring the T18 transmission are "high-hood", clearance for classic Small Block and high Vortec (truck style) intakes and accessories is not a problem.
Novak engine mounts are available to ease the installation of your engine.
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.
Driveshaft length changes may be required. Chevy engines (with their rear distributors) can install around 3" further forward than AMC engines. It is also recommended that LS family engines be installed 3" further forward than the factory block (using the back face of the block as the datum point) for exhaust clearance, firewall access, etc.
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.
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.