NV3550 5 Speed Conversion into a Wrangler with Ford V8

NV3550 Conversion

Package Pricing below

The NV3550 is an excellent option to consider in smallblock Ford V8 (289-302-351 Windsor series motors) Jeep applications. It will comfortably handle a mild V8 in a vehicle such a as a Jeep, and will fit under the body in a Jeep with very few additional modifications.

NV4500 Conversion

There is one other popular replacement option for these Jeeps: The NV4500. This trans is way-oversize for the application, and requires a body lift or extensive floor pan modification to fit. The usual incentive for this conversion is to get the truck style wide ratio, almost granny 1st gear which can be useful for offroad use. On the other hand, this conversion will make a your jeep drive more like a  truck. If this looks like the option or you, High impact does have available a package using the NV4500. Call or email us for a free quote.

NV3550 Conversion Details

Conversion Package

High Impact has available a package providing you with all the primary essential ingredients to this installation. The NV3550 will fit under the stock body without a body lift. Only minor floor pan mods are needed where the shifter handle comes up.

Adapting To The Transfer Case

NP231 – This is the transfer case found stock in Jeeps from 1989 – 2000, and most jeeps (except Rubicon) from 200-up. Some 87-88 Jeeps will have the 231. Units that came with the 2.5L 4 cyl engine, and units that came behind the Peugeot 5spd (1987-88) will have 21 spline input gears. If you wish to retain this transfer case, you will need to replace the input gear with a 23 spline part (Listed below). The remainder of the NP231 Tcases came with a 23 spline input, and will bolt up directly to a NV3550 transmission

Atlas II Transfer Case – This case is available in configurations for direct bolt up.


Parts can be purchased separately also.

# NV3550 into Jeep with Ford smallblock PKG Total-> $1,660.34
1 Rebuilt NV3550 Jeep 5spd 4WD Transmission. NO CORE CHARGE $1,290.00 $1,290.00
1 Shift Handle (NV3550) $25.43 $25.43
1 Shift Tower $55.00
Installation kit: This kit is designed to work with a standard Ford car/truck-type BH with a 4.848 index dia.. The transmission has a different dia input shaft, thus the clutch disc will need to be changed. It is always recommended to use a fresh throwout bearing, and it is a good idea to replace the pressure plate unless you know it is fresh
1 Ford BH adapter kit, incl new clutch disc (works with a stock Ford bellhousing. Listed below if you do not have one) $258.16 $258.16
Adapting to the transfer case: You will need to select the needed adapter components below
NV3550 to Dana 18/20 adapter $401.17 $0.00
NV3550 to Dana 300: The Dana 300 will bolt up, however the bolt pattern rotation in the NV3550 will likely cause the D300 to hang excessively low. This can be corrected by using a gasket as a template and re-drilling the pattern in the adapter of the NV3550. If preferred a bolt on rotation adapter is available:
Option: Dana 300 Rotation Adapter kit. (3/4″ thick) $200.61
NV3550 to NP231 – In most cases a Jeep NP231 case will bolt up directly. The exception: A 231 from behind the 87-88 Peugeot 5sped and a 231 from a 2.5L 4cyl app will have a 21 spline input. This gear will need to be changed to the 23 spl part.
1 (NP231) Tcase shifter bracket/linkage $34.40 $0.00
NP231 input gear, 23 spline, 1987-94 #N/A
1 NP231 input gear, 23 spline, 1995-up #N/A $0.00
NV3550 to NP207 – The NP207 was used in some Jeeps 1987-88. Most will bolt up directly, however some will have a 21 spl input gear. In this case, the input gear must be replaced with the 23 spl part. $190.00 $0.00
Usually the stock pressure plate and T/O bearing will work. Parts known to work in this system specified below. These parts should be replaced if not fresh.
1 Throwout bearing $42.25
1 Pressure Plate $2,300.00
1 Crossmember adapter plate – CJ & Peugeot 4 bolt (on trans)  to 2 bolt mount adapter $34.40 $31.76
Other Items you may need:
Flywheel $245.00
Dust shield/engine plate $65.00
Ford Bellhousing $250.00
Dust Boot $8.00
Fork $22.00
Master cyl $160.00
Slave Cylinder $70.00
Hydraulic Hose