Chevrolet & GM Generation I-III+ Engines
Jeep AX15, NV3550 & NSG370 Transmissions
With the advent of quality five and six-speed transmissions in Jeeps, we now offer the possibility of marrying them to various Chevy and GM engines in a straightforward and sanitary manner using our block-to-bellhousing style adapter assembly.
This plate style adapter is precision laser cut and machined. Included are the adapter, fastening hardware and instruction guide.
Precision CMM mapped and machined dowel locators and fastening points assure total concentricity for long transmission life.
The adapter is plated in black zinc for corrosion resistance and appearance.
This adapter is compatible with the:
This kit will work with either the earlier AX15 that uses the concentric, internal hydraulic throwout bearing, or the later style AX15 that uses the external slave cylinder.
The following Chevrolet & GM engines are compatible:
*Big Block V8's or other engines may not be appropriate for the strength of certain transmissions.
The adapter is easily and quickly installed onto the engine and transmission.
Choosing Your Pilot Bushing
Depending on the transmission you have and the engine you choose, your pilot bushing will vary. See our Pilot Bushings page to choose this critical component for your conversion.
For GM engines prior to the Gen. III+ Series (LS & Vortec, 1997- present), you will use your GM / Chevrolet flywheel as per factory to your engine, which can be either the 153 tooth version or 168 tooth versions.
If you are using a GM Gen. III+ engine, we strongly recommend the use of our extended height LS / Vortec flywheel to normalize the clutch system.
|This is the right and recommended GM Gen. III+ flywheel to use to standardize the clutch assembly, and acheive proper clutch geometry and release action.|
Clutch Assembly & Release Bearing
You should use a standard GM pressure plate and clutch disc kit of your choice. This adapter assembly is intended to work with all known factory height pressure plates, when used in conjunction with Novak's innovative adjustable throwout bearing for 1994 - 2006 external slave style bellhousings.
|Novak's adjustable GM release bearing is the ultimate answer to setting up an optimal conversion or factory style clutch system.|
If you are adapting to an earlier internal concentric hydraulic release bearing, you need to pay close attention to bearing height and release action, and space it to modify if necessary.
Engines & Engine Mounting
These Jeep transmissions are likely to be relocated as much as 3" forward when attached to most V6 & V8 engines, due to firewall vs. block/head differences in the GM engines vs. the I6 engines. This is not difficult and shifter stick modifications (instructions included) are recommended to avoid body tunnel modifications and to keep your factory console and boot in the same location.
|Novak's MM Series engine mounts, featuring excellent vibration dampening, superior strength and impressive adjustability - adjustable even after the engine is installed. The design and strength and affordability of our mounts are second to none.|
The Novak engine mounting system offers the best designs on the market for strength, ease and flexibility of installation. Whether you are installing a classic Small Block, a V6 or a Generation III powerplant, we've got you covered.
Novak offers what we have found to be the most intelligent engine mounting system for Jeeps available, allowing the installer to make an easy and satisfying decision as to powertrain placement with the new engine, AX15 transmission and NP / NVG transfer case all considered.
For your GM engine, we will suggest the use of our RadLock high-performance conversion radiators, which are rugged, easy to install and are extremely efficient in cooling in even the most demanding environments.
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.
|Novak's #375 kit as installed on a GM 5.3L Vortec engine.|