Trans cooler installation.
Hi all, I wanted to be proactive to see if I could keep my automatic tranny alive for the long haul. I have a 27 ft Chateau sport with the 4R100 trans. I am the second owner and decided to bite the...
Forum Discussion
TNRIVERSIDE wrote:
If your additional cooler is in series with your factory cooler it should not let the trans run too cool. The factory trans coolers have a thermostat to not allow the fluid to circulate through the cooler until the trans gets to the operating temp. It will then open and close to regulate the trans fluid at the correct temp.
The factory 4R100 DOES NOT have a thermostat! Ford never installed any type of thermostat on the 4R100 transmission. That started with the replacement for the 4R100, the 5R110 TorqShift.
You may be thinking of the pressure bypass on the side of the 4R100. That is designed to open if the cooling circuit is restricted. It won't open due to cold temperatures until way below 0°F. With synthetic ATF it will never open due to cold temperatures.
