Description

Overview

This caliper tappet and boot 74mm kit helps restore precise adjustment in Knorr SB trailer disc brake calipers. It replaces worn tappet hardware and the protective boot so technicians can set pad clearance accurately again. As a result, the foundation brake package can deliver more consistent braking across heavy vehicle axles. In addition, the kit supports preventative maintenance programs where downtime and uneven pad wear are a concern.

Features

This kit combines a replacement tappet and matching 74mm boot for SB calipers, so the contact area and seal profile remain compatible with the original design. Firstly, the boot helps shield the tappet from road grime, spray and general contamination. Secondly, the matched components support smooth manual adjustment during brake service. Finally, the design suits workshop use on modern air braked trailers that run Knorr SB calipers.

Specifications and Materials

Part number: FB2878.
This caliper tappet and boot 74mm kit is designed for Knorr SB air disc brake calipers that use a 74mm tappet head. The tappet provides the mechanical interface between the caliper adjustment mechanism and the brake pad backing plate. Meanwhile, the boot acts as a flexible barrier that reduces the ingress of dust and moisture around the tappet area. For general engineering context on foundation brake hardware, refer to this foundation brake overview

Compatibility and Fitment

This caliper tappet and boot 74mm kit suits Knorr SB series trailer disc brake calipers that specify a 74mm tappet and matching boot. It is intended for use on heavy trailers with air disc brakes where the existing tappet or boot shows wear, damage or contamination. Always confirm the caliper family, axle position and service instructions before installation, and compare the removed components with this kit so the contact surfaces and boot geometry match.

Compliance and Safety

Correct tappet adjustment is critical for balanced braking and to keep pad movement within the manufacturer recommendations. Therefore technicians should follow the official Knorr SB service procedures when fitting this caliper tappet and boot 74mm kit. In addition, they should inspect guide pins, pads and discs at the same time to identify any related wear patterns. Always chock wheels, isolate the vehicle and depressurise the air system where required before working on any foundation brake components.

Trailer Applications

Knorr SB disc brake calipers are widely used on modern air braked semi trailers, including general freight, tanker and specialised fleets. This caliper tappet and boot 74mm kit is suitable for workshop environments that routinely service these trailers and need reliable replacement hardware for the adjustment mechanism. Furthermore, it can form part of a scheduled brake overhaul program where fleets replace high wear items together to reduce unscheduled downtime.

Cross-reference and Suitability

No formal cross-reference list is currently available for this caliper tappet and boot 74mm kit. Instead, match the removed tappet and boot against this kit and confirm the caliper type using the vehicle or axle identification plate, then consult your workshop documentation if any doubt remains.

Why Choose ICS Trailers

ICS Trailers focuses on heavy trailer brake components, so you can source caliper hardware that matches real workshop requirements. Our team understands air brake foundation parts and can assist with practical product selection across fleets that use mixed trailer types. For related components, service tools and technical support, we maintain a dedicated range of foundation brake parts for modern air braked trailers. Browse Foundation Brakes at ICS Trailers via our Foundation Brakes category