Is my trans temp too low?
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TECH Junkie
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From: Republic of Texas
Is my trans temp too low? I have a cheapo Hayden cooler, but it seems to be working pretty well. My trans temps rarely get above 180, even got to 210 once after nailing it hard quite a few times. But they are usually around 140 in stop and go traffic. Driving around today it stayed in the 110 - 130 range. The outside temps today was in the 40-50's. I've heard that running too cold can be a bad thing. Yes, I have a converter. Any comments?
Re: Is my trans temp too low? Bravo,
Unlike engine oil, ATF fluid is best left cool. The general "redline" on ATF fluid is in the 230-250 degree F range, so it's best to always keep the fluid cooler than that. I'm not positive about the autos in our cars, but I know on my dad's truck (a 500 hp diesel powered monster with an auto) the fluid is always circulated through the cooler, so running down the road the needle just sits on the peg. In the summer however, when towing our racing trailer, the temps can get into the very hot range (240ish). We use synthetic (amsoil) tranny fluid, though, and keep it changed often, so it's not so bad on it, and we have an auxilliary cooler to do the most possible to keep its temperature down. There's a heirarcy published by most of the oil companies that shows how tranny fluid's life drops as it is exposed to hotter and hotter temps. At no hotter than 210, it'll last 30k miles easy. The hotter the fuild gets the harder it is on the seals, gaskets, and the valve body. But, to answer your question, staying cool is not at all bad for the fluid... it helps!
John
Unlike engine oil, ATF fluid is best left cool. The general "redline" on ATF fluid is in the 230-250 degree F range, so it's best to always keep the fluid cooler than that. I'm not positive about the autos in our cars, but I know on my dad's truck (a 500 hp diesel powered monster with an auto) the fluid is always circulated through the cooler, so running down the road the needle just sits on the peg. In the summer however, when towing our racing trailer, the temps can get into the very hot range (240ish). We use synthetic (amsoil) tranny fluid, though, and keep it changed often, so it's not so bad on it, and we have an auxilliary cooler to do the most possible to keep its temperature down. There's a heirarcy published by most of the oil companies that shows how tranny fluid's life drops as it is exposed to hotter and hotter temps. At no hotter than 210, it'll last 30k miles easy. The hotter the fuild gets the harder it is on the seals, gaskets, and the valve body. But, to answer your question, staying cool is not at all bad for the fluid... it helps!
John
Re: Is my trans temp too low? Heh, I have a B&M 24k cooler and in the wintertime (like it is now), with temps in the 10-30s, the gauge needle rests against the peg. Does not exceed 100 degrees unless I've been driving for 30 mins or so. On AutoTap, I usually show ~75 degrees or so.
I don't think you can get 'too' cold until you start going below freezing or something. You generally want the temps to NEVER exceed 200 degrees.
Dope
I don't think you can get 'too' cold until you start going below freezing or something. You generally want the temps to NEVER exceed 200 degrees.
Dope
