Adapting the

Willys Jeep L & F 134 Engines

to the

Dodge NP435 Transmission

This adapter assembly joins the Willys I4 engines - the L-Head 134 and F-Head 134 - to the Dodge NP435 four-speed transmission. This assembly is used to replace the T90A and T98 transmissions as found in 1945-1971 Jeep vehicles.

Product & Features


The 1435 plate style adapter is machined of a 6061T6 billet aluminum alloy, featuring an integrated precision machined bearing retainer. The adapter is ~5/8" thick, and when used in conjunction with the Novak #432 adapter, makes for a ~14-7/8" long transmission package (bellhousing face to transfer case face). 


The kit includes the adapter plate, Jeep bellhousing locator / throwout sleeve, clutch disc, pressure plate, release bearing, selective gaskets, pilot bushing, seal, hardware, and instructions.

Applications & Compatibility


Only the NP435 from Dodge trucks is compatible with this conversion, and only the more common tapered-front bearing (not the early roller ball bearing versions). The Ford NP435 is NOT compatible with this conversion.

134 Bellhousings

The cast-iron 134 bellhousing is retained and used with this conversion. It requires no modifications apart from a simple thread clearance operation with a drill.


Clutch Assembly 

Your factory clutch release arm will be retained. Included in the kit are the new pressure plate, clutch disc, release bearing, and pilot bushing. You can use your existing Jeep's factory style release system and pedal.

Jeeps & Engines

Generally this assembly is used to replace the T90A and T98 transmissions as found in 1945-1971 Jeep vehicles.

Related Products



Installation Requirements


Normal mechanics tools along with a dial indicator to set end play on the transmission will be required. Instructions are included.


Driveshaft length changes are often required. Most conversions to these transmissions will require that the rear driveshaft be modified to be shorter and front driveshaft longer. Some of our customers, fearful at the perceived expense of new or modified driveshafts, attempt to let the existing driveshafts dictate engine, transmission and transfer case location, usually to the detriment of the project. Our recommendation is to always value the correct position of drivetrain components over saving a few dollars which is usually regretted in the long run with compromised positioning. Sometimes the application allows use of the existing shafts without modification. While that is perfectly acceptable, it should not be the first priority. Driveshaft modifications and rebalancing can be affordable when performed by driveline, RV or tractor implement specialists. New driveshafts are an option, but not necessarily a requirement in regards to the actual successful conversion if your existing driveshafts are in good condition. 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. Novak can also accommodate your needs on this if provided with dimensions for the shafts at a reasonable rate.


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.

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