Symptoms
A soft or sinking pedal, a truck that no longer 'stops on a dime', or brake fluid on the backing plates and rims.
The fix, step by step
- Expedition Imports' procedure: block the truck, pull the wheels, then jack the drums off with two metric bolts in the threaded holes.
- Turn the tension pins 90 degrees to release the shoes, unhook the springs, and disconnect the brake line (removing the bleeder gives more room).
- Through the cut-out in the wheel flange, remove the 12 bolts holding the backing plate and take out the wheel cylinders.
- Don't hone them: rebuild good cylinders and have pitted ones sleeved.
- Fit new hoses while you're there, bleed, and set the shoe adjustment cold.
Tools & part numbers
- Two M10 bolts to pull drums
- two pairs of needle-nose pliers
- flare-nut wrenches
- brake bleeder. Rocky Mountain Moggers lists wheel cylinder kits 000 586 02 88 (front) and 000 586 03 88 (rear), and linings 404 421 13 10.
Where to buy the parts
Front wheel cylinder repair kit (000 586 02 88)Expedition Imports ↗Amazon ↗
Rear wheel cylinder rebuild kit (000 586 03 88)Expedition Imports ↗Amazon ↗
Unimog 404 brake shoe set, 6 mmExpedition Imports ↗Amazon ↗
Brake hose set, 404Expedition Imports ↗Amazon ↗
Hunting a used or discontinued part? Search eBay Motors for Mercedes-Benz Unimog 404 parts →
Rated for a competent home mechanic with a decent tool kit. Confirm torque figures, fluids and procedures against the factory service manual for your VIN, support the truck on stands rather than a jack, and work at your own risk (disclaimer). Some parts links are affiliate links, which pay us a small commission at no cost to you.