Free shipping on eligible orders of $100 or more. Oversized and freight items excluded.

Shop parts / UMI Performance / New

UMI Performance 78-88 GM G-Body C5/C6 Front Brake Conversion Hubs Bearings Bracket Kit

UMI Performance · New

UMI Performance 78-88 GM G-Body C5/C6 Front Brake Conversion Hubs Bearings Bracket Kit

MPN 304647 · Store SKU umi304647

$579.99
IN STOCK1 ready to ship

Supplier stock checked 11/8/2026, 10:02:34 AM UTC. Adding a part does not reserve it.

30-day returns for unopened, unused new parts

Request a return within 30 calendar days after delivery. New parts must be unopened and unused.

Shipping & returns ↗This policy does not limit rights required by law.

Free standard shipping on eligible parts orders of $100 or more. Oversized and freight items excluded. Fitment, taxes, availability and final totals are confirmed before payment.

Product details

UMI’s C5/C6 conversion kit includes laser cut UMI conversion brackets, light weight USA made aluminum hubs and premium bearings. P/N 304647 includes everything needed to adapt the C5/C6 abutment brackets, calipers and rotors to the G-Body spindles. The hub features 5 x 4-1/2 and 5 x 4-3/4 bolt patterns and is intended to face mount the C5/C6 brake rotor in exact factory location (front track width is unaffected). The kit includes premium bearing cups and cones along with the correct rawhide seal for great performance and reliability. The 304647 kit is the choice for UMI’s Green Machine and has been thoroughly tested to withstand road race and auto-x competition. 100% manufactured in USA as well as tested and raced out of Philipsburg, PA – USA. Kit includes: UMI conversion brackets, driver and passenger side aluminum hubs, correct bearings and seals to mount the C5/C6 calipers and abutment brackets. Wheel studs are not included, 1/2-20 threaded studs will be required to complete installation. Determine stud length after choosing wheel and considering offset, whether or not spacers are required, and after determining wheel flange thickness. Kit requires C5 or C6 calipers, rotors, brake pads and brake lines. A detailed list of GM part numbers is included. Requirements: C5 brakes require a minimum of a 17” wheel for clearance while C6 requires an 18”wheel. Please research wheel fitment before purchasing. Mounts 1997-2013 C5 or C6 front calipers and rotors to the 78-88 GM G-Body factory spindle. Conversion brackets are CNC laser cut from 3/8” thick mild steel and feature a heavy duty black powder coat finish. 1978-1988 GM G-Body C5/C6 Front Brake Conversion Hubs, Bearings, Bracket Kit

Manufacturer fitment & guides

Check 304647 against the manufacturer’s application information below.

A manufacturer application guide is not available for this listing. Request the exact application from JuiceBuilt before payment.

Part-specific notes

  • California Proposition 65: Y
More from UMI Performance ↗See the JuiceBuilt workshop ↗

YOUR NEXT MOVE

Your cart.