Any benefit to blocking atf cooler in winter?

[byez]

Would there be any benefit to blocking the air off to my atf cooler during the cold winter months? Does atf have an optimal operating temp range?

Unit in question is an oem air to atf fluid cooler.

 

[JustinH]

Yes it does have an optimal temperature, and up in canada you might want to block it off with some cardboard or something similar.

The first thing to do is monitor the atf temp with a guage, or in some cars you can monitor the temp through the obd2 port.

 

[dwendt44]

Often, the transmission will not lock-up until it's up to temperature.
Shouldn't be a problem during the winter at all.

 

[WalterMitty]

Just be ready to pull over and unblock it if the weather suddenly changes. I didn't do that on a Spring trip (thought I could wait until the end of the day because my engine temps were OK). I overheated the transmission fluid and bought a rebuild.

 

[WishIhadatruck]

Originally Posted By: WalterMitty
Just be ready to pull over and unblock it if the weather suddenly changes. I didn't do that on a Spring trip (thought I could wait until the end of the day because my engine temps were OK). I overheated the transmission fluid and bought a rebuild.



I assume you only had an external trans cooler? My cars all have a water to oil and an air to oil cooler.

 

[unDummy]

If it is an OE cooler, no benefit. Most are undersized anyway.
If it is an aftermarket inline with OE cooling, then feel free to block it off.

 

[rangerdood]

The trans in my Ranger won't allow the fluid to flow through the cooler until the trans is up to temperature anyway. If it's an OE system, I'd say leave it alone.