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Hydrastar 7K Axles, 8 Lug Integral Tandem Axle Trailer Disc Brake Kit (5/8")

Hydrastar® 7K Axles, 8 Lug Integral Tandem Axle Trailer Disc Brake Kit (5/8") {E7K-T5}

SKU
by Hydrastar
$2,413.00 - $2,463.00
$2,413.00
$2,413.00 - $2,463.00
$2,413.00

For Service Manual, Instructions and Warranty Testimonials, Click Here.

Limited Warranty Included
2 YEAREOH Actuator
3 YEARDisc Brakes
LIFETIMEBrake Lines
NEW UPGRADE AVAILABLE - OIL BATH SEAL Select From Dropdown
Go Oil Bath!
Standard Grease Seal
What You Get

In The Box & Sold Separately

Included
✓
(1) 381-7067 — Hydrastar® Electric Over Hydraulic (EOH) Trailer-Mounted Brake Actuator (1600 PSI)
✓
(1) 496-252 — Hydrastar® Hydraulic Tandem Axle Brake Line Kit – 25 ft., 3/16 in., 3000psi hydraulic brake pressure
✓
(4) 25580 — Hydrastar® 6K/7K/8K Rated Inner Bearing
✓
(4) 02475 — Hydrastar® 7K/8K Rated Outer Bearing (5/8 in., 9/16 in.)
✓
(4) 472920 — Hydrastar® 6K/7K/8K Rated Grease Seal
✓
(4) E78-DO — Threaded Sealed Oil / Grease Cap
✓
(2) E303-7K5-A — Hydrastar® 7K/8K Rated, Dacromet Coated Integral Single Axle Brake Kit (5/8 in. )
✓
(2) 303-E7/8R5 7K/8K Axle Rated Integral Dacromet Coated Rotor
✓
(2) 303-E78C 7K/8K Axle Rated Dacromet Coated Integral
✓
(2) 303-7BI 7K Axle Rated Dacromet Coated Bracket
Sold Separately
–
DOT 3 or DOT 4 Brake Fluid
–
Tools for installation
–
Hubs & Drums (use existing)
Questions about fitment?

Feel free to reach out to us or start a live chat in the bottom right corner for assistance.

Additional Details

Specifications & Compliance

•
Durable, sealed, fully enclosed extruded anodized aluminum housing case to easily withstand the environmental and road demands (not cast or plastic).
•
The Hydrastar® Brake Line Kit includes: – Brake Lines – Fittings – Required Hardware
•
Corrosion resistant, high-performance alloy tubing backed by a Lifetime Guarantee.
•
Triple annealed and eddy-current tested, Hydrastar® brake lines are walled 40% thicker preventing kinking and allows simple routing and smooth bends without bending tools required.
•
Meets SAE J1650 Standards (0.028 in.)
•
Made in USA

What You Need To Know

  • 2 YEAR LIMITED WARRANTY from date of purchase.
  • Complies with CFR-393 Federal Braking Requirements and meets all Department of Transportation (D.O.T.) regulations.
  • Designed for Drum and Disc Brakes with reliable 12 V DC operation and solid-state electronics.
  • Color-coded, heavy duty 12 Gauge wire for easy and quick install.(Black/Constant power, Blue/Brake controller, White/Ground, Yellow/Break-away)
  • 4 ft. Wire, Enough Length to Customize Any Job.
  • Required use of D.O.T. 3 or 4 Brake Fluid. (Not included.)
  • Compatible with any trailer configuration with 1-3 axles.
  • (2) E303-7K5-A –Hydrastar® 7K/8K Rated, Dacromet Coated Integral Single Axle Brake Kit (5/8 in.)
  • Corrosion-resistant Dacromet Coated Rotor and Bracket for Industry Standard trusted performance.
  • Premium, corrosion-resistant Stainless Steel Caliper construction for reliable performance.
  • 5/8" in. wheel studs
  • 5-Bolt Brake Flange
2024–2026 GM Truck & SUV Owners

Dashboard showing “Service Trailer Brakes”? Brakes disabled?

Affects Silverado, Sierra, Tahoe, Suburban, Yukon, Escalade, Colorado, Canyon & Hummer EV with integrated trailer brake controller.

That’s a known GM compatibility issue across the 2024–2026 lineup. Hydrastar has the fix — the GM Diode Module (#381-7074) is a plug-and-play inline solution.

New Ford Truck Owners

Connectivity issues before or after the dealer flash? Brakes dropping in and out?

Affects new Ford trucks when switching from electric mode to EOH mode.

Our Hydrastar Controller Adapter Module (#381-7073) has been very successful resolving this for Ford owners. Note: this is not a Hydrastar issue — just a Hydrastar part that helps.

Need Help Choosing?
Our team has helped thousands of trailer owners find the right setup.
Fastest response? Use the chat bubble in the bottom-right corner ↘
or call (812) 655-4544 · Mon–Fri, 8am–4:30pm ET