Here's a bit of info for people debating the whole "before" or "after" the original cooler. Take it for what it's worth.
Tru-Cool LPD Transmission cooler kits
# Medium Duty 3/4 thick coolers
# Tru-Cool self-regulating coolers - it is the oil that regulates the cooler.
# Thicker oil that is below the ideal operating temperature bypasses the cooler through the upper two plates. When the temperature rises, it becomes thin enough to pass through the entire cooler. TRU-COOL's superior heat transfer is efficient & automatic.
# For use with 5/16 & 3/8 transmission cooler lines only.
# Includes standard installation kit shown on bottom of this page.
# *Some late model cooler applications may require additional fittings when installing a cooler kit.
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