NV3550 conversion

We have nahd a number of customers who have desired to replace their 3 speed automatic with a 5speed manual. One reason is the 5 speed has overdrive and the 3 speed does not. Another reason is that for whatever reason, they prefer a stick.

The NV 3550 is considered to be the best stick trans ever supplied with a jeep. This package is for 6 cyl jeeps, if you have a 4 cyl automatic, you will need the kit NV3550 replacing a AX5, and we will need to add a flywheel to that kit.

Automatic trans with Overdrive

Note: If your aim is to add overdrive, but you would prefer to stay with an automatic, we have a package to install a non-computer 700R4 automatic OD trans into a Jeep wrangler. (The Jeep OD automatic requires a computer. We can use the Jeep AW4 if you want a full manual conversion)

NV4500 Conversion

There is one other popular 5 speed conversion 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 1^st 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 replacing the AX15.  

NV3550 / Klune-V Extreme underdrive

Rather than a granny gear 4 or 5 speed, a more "premium" alternative to achieve extreme gearing would be an NV3550 combined with a Klune-V Extreme Underdrive.

NV3550 conversion Details

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

Dana 300 - Note: NV3550 tail is drilled to fit NV231. D300 will fit, however will be rotated Down approximately 9 deg: Tailhousing will need to have 6 holes re-drilled. If desired, a rotation adapter plate kit s available to make this a bolt together.

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

Klune-V Extreme Underdrive - This unit is a premium option where extreme offroad gearing options are desired. The unit fits between the transmission and transfer case. Due to the additional length when adding this unit, there are various issues that must be addressed to ensure proper driveshaft operation. While all options are not discussed, an article installing a Klune into a Wrangler YJ will give an overview. Other options combining a Klune-Atlas or Klune-Bronco Dana20 make shorter, no-compromise systems. Please call us if you are considering such a system and have concerns not covered in the website. 

Conversion Package

High Impact has available a package providing you with all the primary essential ingredients to this swap. 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 (you will need to cut a hole and install a boot)   

Package:

*NOTE: The prices below are PACKAGE prices: The prices for the installation kit parts will be 10-20% higher when purchased separately

Different Packages for both the internal and external slave versions of his kit are listed below.

(We can also provide custom packages where needed)