What is the Difference Between 3.5K and 4.4K Electric Trailer Brakes

Updated 03/13/2018 | Published 03/12/2018

Products Featured in This Question

etrailer Electric Trailer Brakes - Self-Adjusting - 10" - Left/Right Hand Assemblies - 3.5K

(2807)

$155.37

Mounting Hardware for 10" Brake Assemblies

(400)

$17.09

Question:

I have an open deck, tandem axle trailer with 15inch tires and 10inch x 2.25, electric drum, non-self adjusting, trailer brakes. One of my trailer brakes is damaged beyond repair so I would like to upgrade to self adjusting brakes on both sides. I cannot find any axle tags or tongue identification on what grade my axles are. What are the differences between 3.5k trailer brakes and 4.4k trailer brakes? Are they same bolt pattern to the axle? If my brakes were 3.5k brakes can I install 4.4k brakes and expect better braking?

asked by: S. P

Expert Reply:

Most of the time brakes of the same size but with different capacities have different magnets. A larger magnet is needed for a higher capacity. If you were to go to larger capacity brakes they may seem too aggressive for the load. In that case you can reduce the power output from the brake controller.

A 4,400 pound axle is not all that common so I am willing to bet that you have 3,500 pound axles. The ideal set of self-adjusting 10x2-1/4 inch brakes for you is # AKEBRK-35-SA. I have linked a video review for you.

Chances are you will also need to replace the nuts that hold the brakes on. For that you can use # BRKH10B. It comes with 8 nuts and 8 lock washers.

expert reply by: Michael H