Wet Spline - Chelsea Products Division | Parker US
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Chelsea Solutions

Wet Spline is a specialized lubrication design to enhance the performance of hydraulic pump shafts when using direct mount pumps. By providing a constant flow of clean and fresh oil to the PTO and output shafts, Wet Spline effectively prevents premature fretting on the spline shaft. This results in increased durability and reliability of the hydraulic system, reducing maintenance costs and downtime. Wet Spline ensures optimal lubrication and protection, even under extreme conditions.

Eliminate Spline Fretting and Extend the Life of your PTO and Pump Shaft

Premature spline fretting is often caused by the torsional vibrations found in today’s high torque, low RPM engines. As engine speed goes down, the amount of vibration of the PTO and pump splines increases. This condition is more even more exaggerated when the PTO is disengaged and there is low load on the mating shafts.  Wet Spline provides a constant flow of fresh, clean oil to the mating PTO and Pump shafts. This is done during all phases of operation but most importantly when the PTO is disengaged.

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Field-Proven to Increase Pump Shaft Life

Wet Spline reduces maintenance down time and increases pump shaft life by 7-10 times. This technology is field-proven over many years in military applications and commercial vehicles including refuse, yard spotters, material handling, aerial, and more! 

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Reduced Maintenance Time

Why Choose a PTO with Wet Spline

Prior to Chelsea’s launch of Wet Spline technology, pump shaft lubrication used to be a manual process as part of the routine maintenance schedule. Every 2-3 months, pumps were to be removed from the PTO, and mating shafts were to be thoroughly cleaned and freshly greased, before reinstalling the pump and retorquing to specifications. Chelsea's Wet Spline solution eliminates this time-consuming task! This means increased uptime and keeps your trucks on the road.

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