Forum Discussion
_40Fan
Aug 16, 2015Explorer
These valves are stupid easy to diagnose, but what makes them hard for the newer techs is that the computer/scanner won't tell them it is bad.
Warm up the truck and transmission. TOUCH the line coming out of the trans to the valve. Is it hot? Yes means the hot fluid is flowing out. Is the line going into the trans feel the same temp? Valve is just circulating the fluid and not sending any towards the radiator. Heck, can even pull the return line off at the transmission and the return line coming off of the radiator (before valve) and see where the flow is going!
Warm up the truck and transmission. TOUCH the line coming out of the trans to the valve. Is it hot? Yes means the hot fluid is flowing out. Is the line going into the trans feel the same temp? Valve is just circulating the fluid and not sending any towards the radiator. Heck, can even pull the return line off at the transmission and the return line coming off of the radiator (before valve) and see where the flow is going!
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