Parts Needed to Upgrade From 7K to 8K Axle and Convert to Electric Over Hydraulic Brakes

Updated 06/03/2020 | Published 09/05/2018

Products Featured in This Question

Kodiak Disc Brake Kit - 13" Hub/Rotor - 8 on 6-1/2 - Dacromet - 7,000 lbs

(18)

$730.32

Hydrastar Electric Over Hydraulic Actuator for Disc Brakes - 1,600 psi

(242)

$945.94

Hydrastar Hydraulic Brake Line Kit - Tandem Axle - 25' Long, 3/16" Main Line

(39)

$256.43

Kodiak Disc Brake Kit - 13" Hub/Rotor - 8 on 6-1/2 - Dacromet - 8,000-lb Dexter Axle

(4)

$770.97

Question:

What parts do I need to change the 7K axles to 8K axles PLUS convert the existing electric brakes to electric over hydraulic kodiak disk brakes? Cost? 2016 Momentum 350M fifth wheel with tandem axles- 8 bolt 9/16 lugs, 16inch tire TRUCK- 2016 GMC 3500HD with intergated brake controller

asked by: DOUGLAS L

Expert Reply:

In order to change from an 7,000 pound axle to an 8,000 pound axle you will need to replace the entire axle with an 8K model. You will not be able to add any parts to your current axle to upgrade it to an 8,000 pound capacity. We do not currently have any 8,000 pound axles available but you will want to find one that features the same hub face and spring center length to what you currently have.

Then in order to convert from electric drum brakes to electric over hydraulic disc brakes you will need disc brake hub and rotors, a brake line kit, and an electric over hydraulic actuator. Finally you will want to make sure that the factory brake controller on your Sierra is compatible with electric-over-hydraulic brakes.

We have 8,000 pound hub and rotor kits like the Kodiak Dacromet # K2HR858DD that includes two full brake assemblies and the needed mounting bolts. We also have tandem axle brake line kits like the HydraStar # HS496-252 that should work well. Then for an electric over hydraulic actuator I really like the HydraStar # HBA16.

I have attached a great article that goes into further detail regarding all the parts needed to add electric-over-hydraulic disc brakes to a trailer that you can check out as well. Pricing information will be located on the specific product pages.

expert reply by: Chris R

Greg A.

5/30/2020

I want to change out 7000 lb tandem axles to 8000 lb tandem axle can I do that with just changing the u-bolts. Thanks

Chris R.

6/3/2020

You'll need to replace the hub and brake assemblies as well if you're wanting to upgrade the whole setup to an 8K capacity. Replacing just the axle itself won't increase your weight limit since your existing hubs would still be rated for 7,000 pounds.