Overview
The Baer Brakes 4302333S is a silver rear brake kit from the SS4 Plus line, pairing a four-piston S4 caliper with a 13 inch two-piece slotted and drilled rotor. The kit is built for a GM small pattern 10/12 bolt housing with bearing on axle and a 5×4.75/5×5.00 wheel bolt pattern. The axle flange and bolt pattern are the main compatibility references, so confirm fit for your vehicle’s year, model and trim before ordering.
Baer’s backing plate serves as the caliper mount and also houses a one-piece park brake shoe assembly, so the parking brake is part of the rear housing itself. The kit uses the DR1-C pad type and comes with stainless braided hoses. It is a performance-grade rear disc setup for owners working with a GM 10/12 bolt bearing-on-axle housing.
Key features
- Silver powder-coated S4 four-piston caliper, manufactured in Phoenix, Az
- Hard anodized aluminum pistons with stainless steel abutments and noise suppression clips
- Dual dust, weather and pressure seals
- Two-piece slotted, drilled, zinc-plated 13 inch rotor on a billet aluminum hat
- Rotors arrive pre-assembled with NAS high grade stainless hardware
- Caliper body CNC machined from US sourced forged or billet aluminum
Choosing a rear brake upgrade
A rear disc kit replaces the drum or disc hardware at the axle end, so it changes how the parking brake works. When the park shoe sits inside the backing plate, cable routing and adjustment become part of the setup, and that work should be planned before the rotor and caliper go on. Hydraulic lines also need to reach the new caliper without rubbing suspension or axle components.
Rotor and pad choices affect braking under load. A slotted, drilled rotor sheds heat differently from a plain one, and pad compound should match how the vehicle is used on pavement and trail. Brake fluid should be fresh when the system is opened, and bleeding should follow a set sequence so no air remains in the rear circuit.
After installation and a short test on flat ground, re-check lug torque, caliper bolts and hose clearance. Inspect the rotor face for cracks, heat spots and uneven wear, and replace pads when the friction material is thin or the surface glazes. Upgrades often include the front brakes too, so balance the rear setup with the front before heavy towing or rock crawling.
- Plan park brake cable routing before mounting the caliper
- Use fresh fluid and bleed the rear circuit in sequence
- Re-check lug torque and caliper bolts after the first drives
Specifications
| Brand | Baer Brakes |
|---|---|
| Part number | 4302333S |
| UPC | 844165028772 |
| Axle | Rear |
| Axle flange | GM small pattern 10/12 bolt, bearing on axle (hybrid) |
| Wheel bolt pattern | 5×4.75/5×5.00 |
| Lug count | 5 lug |
| Caliper | S4, four-piston, fixed |
| Caliper color | Silver |
| Pad type | DR1-C (FMSI DR1-C) |
| Rotor outside diameter | 13.0 inch |
| Rotor thickness | 0.81 |
| Rotor type | 2-piece, vented |
| Rotor material | Iron with aluminum hat |
| Rotor surface | Slotted, drilled and zinc plated |
| Minimum wheel diameter | 17.0 inch |
| Brake hose | Steel braided, DOT approved |
| Park brake | Included |
| Template | S135H |
| Emission code | 6 |
| Grade | Performance |
| Country of origin | US |
Vehicle fitment
It is a rear axle kit with a GM small pattern 10/12 bolt bearing-on-axle flange. That flange pattern is used on Buick, Olds and Pontiac applications.
Axle flange patterns other than GM small pattern 10/12 bolt bearing on axle do not apply to this kit, and front axles are not covered. Confirm fit for your vehicle’s year, model and trim before ordering.
Installation notes
Park brake cables are not included, so plan for the cable setup separately. Baer recommends comparing the S135H template with the wheel you intend to use, since wheel style and manufacturer can affect clearance. Rear brake work should be left to a qualified technician.
What’s included
The kit includes the S4 four-piston caliper, the Baer backing plate with its one-piece park brake shoe assembly, the 13 inch two-piece rotor with pre-assembled stainless hardware, and stainless braided hoses with hardware.
Not included: Park brake cables, lug nuts and a front rotor.
