On my 2015 mustang i have started leaving the instrument cluster display in gauge mode, when the trans is fully up to temp it seems to run around 203 degrees when i put the a/c on within around 10 minutes the temp drops an average of 20 degrees, which to me makes sense with the fans running constantly pulling more air past the cooler. Never really heard mention of this before, so guys trailering heavy loads would it not be in your best interest to run the a/c steady.??
Running A/C drops transmission temps.
- Thread starter hemitom
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Maybe if you're puttering around town, but if you're at highway speeds, the fans shouldn't be running. Either way, 200 degrees isn't much of a challenge for fluids today.
More A/C demand is probably keeping the cooling fans on for longer, or spinning faster
Trans cooler in the front, or in built with the radiator would explain the behavior
I know my Camry in 100° bumper to bumper traffic won't go past 183° (coolant) simply because both fans are going full speed steady
Turn the A/C off, coolant and trans temps begin to rise, as the fans are now only driven by coolant temps
Trans cooler in the front, or in built with the radiator would explain the behavior
I know my Camry in 100° bumper to bumper traffic won't go past 183° (coolant) simply because both fans are going full speed steady
Turn the A/C off, coolant and trans temps begin to rise, as the fans are now only driven by coolant temps
It can be good for transmission fluid to get hot enough to cause any moisture to leave it every once in a while. If too much moisture ends up in transmission fluid, some transmissions have some metal parts that can rust, and that rust can interfere with the proper operation of the trany. Years ago an uncle of mine had a mobile home that had its own engine and trany, and the transmission failed, and when it was taken apart rust that blocked passages was found and he was told that the rust was the reason for the failure.
As soon as the AC is switched on the engine cooling fans come on. They're also pulling air through the transmission cooler as well, depending on where it's mounted. Having said that I see no difference in transmission temperatures with my Wrangler. But I haven't ever seen the transmission fluid temperatures over 174F, it usually stays at 170F once it is fully warmed up.
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That's interesting, I've never seen a transmission with rust inside of it, usually the metal is so clean looking (shiny/new). But yeah i guess if it just sits around most of the time it could rust, I guess anything could. I've just never seen rust inside a transmission, usually that fluid has everything coated so well and unlike an engine - where condensation is created so often from the extreme temperature changes from combustion - I've never really seen water/condensation in the fluid, but I'm sure it does happen. Never thought of that.
Every gallon of gas or diesel burned makes a gallon of water, so there's a steady source of moisture going into the crankcase.
No such source in a transmission, unless you're fording streams or launching boats.
That would be true if it were hermetically sealed.
But since transmissions get hot and cool, they're vented to the atmosphere...which contains moisture.
So, yes, moisture gets into transmissions, when they cool and draw in air. Heat drives that moisture out as vapor.
Transmissions that sit for a long time don't get that moisture driven off. So, depending on climate and how long it sits, a transmission can suffer from internal corrosion due to moisture.
Far, far less moisture than a crankcase gets.
And most modern transmissions are not vented freely.
There are valves that don't let air in or out unless there's enough pressure or vacuum.
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