Difference between Fisher and Western 3 and 4 port modules

Here you will find answers to these questions:

1. What is the difference between 3 and 4 port modules?
2. Is the 3 or 4 port module better?
3. What module does my truck need?

4-Port Module
3-Port 3-Plug Straight Blade Kit Link

If you didn't know, Western and Fisher use the same wiring. And now on the Fleet Flex plows, they are also the same as Blizzard and SnowEx. Blizzard and SnowEx only ever had the 3-port modules. In 2002, Western and Fisher moved away from the relay wiring and switched to the isolation module wiring. This is when the 4-port module was introduced. Somewhere around 2009, they updated the modules to the smaller 3-port module. Why 3-port? It is a new design, it is a smaller module and it is easier to find a place to mount it. Does it work differently? No. Basically they are the same operation, but they do not make the adapters to use the older 4-port modules on the newer trucks with LED and HID headlights. Anything prior to that, the 4-port will work just fine and usually are cheaper to buy.

If you want to be up-to-date, buy the 3-port. It fits more trucks and will continue to be used for a long time, from what we can tell. Looking to save a few $ and don't care about moving it to a new truck? Buy the 4-port kit.

4-Port Modules: There are three different 4-port modules. The 26400 with a White Label (the most common) and there were two modules for trucks with Daytime Running Lights. The first was 26401 with a Yellow Label which was replaced with the 27781 Green Label. The 4-port modules have a 1, 2, 3, 4. The (1) is for the control harness, (2) is for the 11-pin light harness and the (3) and (4) are for the headlight adapters. The 4-port is most commonly on 3-plug plows, but with adapter 44658 you can use this on the new Fleet Flex 2-plug plows as well.

3-Port Modules: There are now three different 3-port module kits. The common module is 29070 or 29070-1 with a Green label, or the soft start module 29760, or 29760-1 with a White Label used on '08 Fords and a few other trucks. They now have a 29760-2 that is basically a 29070-1 module and a new adapter in a box for some of the newer trucks. The 3-port modules have an A, B, & C. (A) is for the 11-pin plug that runs out to the grille, (B) & (C) are for the headlight adapter to plug into. If you are using a 3-port module on a 3-plug plow, you will need a 29047 adapter to connect the control harness. There is no extra adapter if it is the Fleet Flex 2-plug plow.

If you have an older 2-plug relay plow and need to install it on a newer truck that requires the module wiring, you can buy the truck side kit and then you will also need plow side conversion kit 28053.

Below are some photos of the modules: