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Complete kit to service your Fleece Performance Coolant Bypass - Includes all O-rings, fasteners, and a new thermostat.
** Two thermostats included to service all production years, you will only use one (1) of the included thermostats when replacing your bypass thermostat. This kit does not include the Cummins thermostat. We recommend the use of a Cummins 190° thermostat in the stock location. The kit includes 3 new square cut O-rings and 1 new standard O-ring.
Looking for proven diesel performance parts that actually fit and perform? We stock hand-selected upgrades for Duramax, Cummins, and Powerstroke platforms — no guesswork, no junk.
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