Hello, I have a jeep with a 4 speed auto transmission. It has an exterior cooler that is not connected to the engine radiator. It comes with no thermostat for the transmission fluid, so the temps stay around 120F to 140F. Looks like 175F to 195F is the normal operating temperature for a transmission. Are there any down sides to the transmission operating at 120F to 140F that could cause an early failure? Should I install a thermostat for the transmission fluid?
Thank you
In an old vehicle I'd say heck yea, the cooler the better. However, in new ones engineers try to design around 185F for emissions regulations so in theory that should be best. OEM cooler? If so I'd say good job engineers. If installed aftermarket cooler... would require research. But splitting hairs really and at the end of day I wouldn't be concerned if it's shifting well.
Yes, it is an OEM cooler. The lower 1/4 of the AC condenser is the transmission cooler, pretty smart design.
as long as it's shifting properly, then I don't think there's a downside.
what is the gist of this video?
Primarily it emphasizes a relationship between operating temperature of ATF and longevity of the transmission.
F.S.
I think he's a bit full of it