High-quality piston seal

In wheel loaders, compact tractors, skid steers, and excavators, a worn piston seal often shows up as slow cylinder drift, weak breakout force, overheating fluid, or “no external leak” power loss from internal bypass. Once a hydraulic piston seal loses lip tension or gets nicked by contamination, pressure bleeds across the piston, and your cylinder piston seal can’t hold load.

For that FridayParts focus on correct bore fit, profile type (U-cup/T-seal styles vary by cylinder), material (commonly NBR/PU/PTFE blends), and extrusion control for high pressure. And we offer high-quality parts at affordable prices—so you can rebuild instead of replacing the whole cylinder.

Quick Symptom Guide

This page includes piston seal kits for Yanmar, New Holland, John Deere diff-lock, Liebherr, and Caterpillar.

SymptomCommon causeFix
Cylinder driftsinternal bypassReplace piston seals
Slow/weak hydraulicsWorn seal + heatInstall the piston seal kit

Send me your machine model and cylinder location (arm/bucket/drive). We’ll confirm the right piston seal or other seal kit fast so you can restore pressure, stop drift, and get back to work.