Overview
The Baer Brakes SS4 Plus rear brake kit, part number 4302438CY, is a Comp Yellow rear disc brake system for GM small pattern 10/12 bolt rear ends that use bearing-on-axle mounting with flush mount bearing housings. It pairs a four-piston S4 caliper with a 13 inch two-piece slotted, drilled and zinc-plated rotor.
A one-piece park brake shoe assembly is housed in the same backing plate that carries the caliper, making the parking function part of the rear carrier. The kit is designed for owners who want a rear brake upgrade in Comp Yellow, mounted behind wheels 17 inch or larger.
Key features
- Four-piston S4 caliper with hard anodized aluminum pistons and stainless steel abutments
- Slotted, drilled, zinc-plated two-piece rotor with billet aluminum hat
- Dual seals for dust, weather and pressure
- Powder coated Comp Yellow caliper finish
- Pre-assembled rotors with NAS high grade stainless hardware
- Steel braided hoses, DOT approved, with hardware included
- Caliper made in Phoenix, Arizona, from CNC machined aluminum components
Trail and street use
Rear brakes do a larger share of work on steep descents when the vehicle is loaded or towing, so the rear setup should be sized to the way the vehicle is driven. A heavier rotor and caliper add mass that the hub and wheel bearings must carry, so the rest of the rear end should be inspected at the same time.
On the trail, rear brakes see frequent cooling cycles and water exposure. Dust seals and caliper bores should be checked after washing or creek crossings, and the parking brake should be tested on a slope before a trip. Pad compound affects how the pedal feels when the pads are cold, so choose a compound that matches the mix of street and trail driving.
- Inspect the park brake shoes when the rear hub is open
- Check hose routing for rub points against suspension travel
- Recheck lug torque after the first few drives
- Keep spare pads matched to the DR1-C type
Specifications
| Brand | Baer Brakes |
|---|---|
| Part number | 4302438CY |
| UPC | 90127952665 |
| Sold as | Kit |
| Caliper | S4, four-piston, fixed |
| Caliper color | Comp Yellow |
| Rotor type | 2-piece, vented, slotted, drilled, zinc plated |
| Rotor outside diameter | 13.0 inch |
| Rotor thickness | 0.81 |
| Minimum wheel diameter | 17.0 inch |
| Axle flange | GM small pattern 10/12 bolt with flush mount bearing |
| Wheel bolt pattern | 5×4.75/5×5.00 |
| Lug count | 5 lug |
| Brake pad FMSI number | DR1-C |
| Brake hose | Steel braided, DOT approved |
| Template | S135H |
| Emission code | 6 |
| Country of origin | USA |
Vehicle fitment
Comp Yellow kit 4302438CY lists no specific vehicles. Match it to GM small pattern 10/12 bolt bearing-on-axle rear ends with flush mount housings, and confirm the 5×4.75/5×5.00 pattern on your hub.
A fitment list is not available for this kit; verify against Baer’s published axle specifications. Confirm your vehicle’s year, model and trim before ordering.
Installation notes
The rotors arrive pre-assembled with stainless hardware, so the rotor and hat go on the hub as a unit. The park brake shoe assembly sits in the backing plate and needs to be inspected when the caliper mount is set. Park brake cables are not included and must be sourced separately. Check the S135H template against the 17 inch or larger wheel you plan to run.
What’s included
The kit covers the Comp Yellow S4 caliper, the 13 inch two-piece rotor on its billet aluminum hat, the backing plate with the park brake shoe assembly, and stainless braided hoses with stainless hardware.
Not included: Park brake cables.
