Thermal bypass valve will kill your transmission change it!
Bros Auto · 174K views · 0:48
Skill Level
IntermediateTime Required
Half dayEstimated Cost
$50–200Equipment
Chevrolet Silverado 1500Permit Required
NoTools Needed
socket set, wrench set, transmission jack, drain pan, gasket scraperGM put out a service bulletin requesting trans thermostat be replaced
during any transmission repair, including Customer Concern Not Duplicated this valve is likely the cause of all the premature transmission failures on the 6l80