3" 50:1 Bare Pumps

RELIABLE DESIGN
Thunder pumps feature a patented, ice-free air motor contained in a rugged housing that is designed to withstand the harshest working environments. ARO is so confident in this design that it is backed by a 5-year warranty

PROTECTED INLET TUBE
Thunder grease pumps have 5/16" inlet holes in the sides of the bottom of the pick up tube. This helps eliminate problems caused by sucking plastic grease drum liners into the pump's lower section

LUBE-FREE AIR MOTOR
The air valves and the piston are pre-lubricated. Thunder pumps do not require an air line lubricator

NO MECHANICAL ASSIST
Thunder's patented valve design uses no trip rods, push pins, or springs. Instead of one mechanical pilot valve in the air motor, Thunder has two independent 3-way spool valves which work together to change the direction of the pump piston

IN-LINE SERVICE
Thunder grease pump air motors can be serviced in the drum using just a standard wrench

FEWER PARTS
Thunder pumps are constructed with 50% fewer parts than the majority of comparable pumps. Fewer parts means less problems

COST-EFFECTIVE DESIGN
Most competitive pumps are too costly to repair after their warranty expires. Thunder's revolutionary design, inexpensive rebuild kits, and field serviceability all add up to a pump that has the lowest cost of ownership in the lubrication equipment market

GREASE COMPATIBILITY
Thunder pumps are compatible with NLGI 0, NLGI 1, NLGI 2 and NLGI 3 grease