Beat the Heat
There's More To
Coolers Than You Think:
It's no secret that heat
kills automatic transmissions. And in high-performance street-strip
applications, the problem is especially acute. Small diameter torque converters
coupled with stop-and-go traffic greatly increase the heat level in an automatic
transmission. In most cases, the extra performance heat under the hood can have
the same effect as heavy loads, trailer towing and desert conditions.
How Hot is too Hot?
The ideal operating
temperature for automatic transmission fluid is between 175º F. At approximately
240º F, important additives in the ATF begin to cook. The result is the
formation of varnish inside the transmission. At approximately 260º F, internal
transmission seals (which are typically manufactured from a polyacrylate
material) begin to harden. The end results are leaks, both internal and
external, simply because the seals lose their elasticity. At approximately 295º
F, transmission clutch plates begin to slip because the oil is breaking down
further. At approximately 315º F, seals and clutches effectively burn out.
Carbon forms in the oil and for all intents and purposes, the transmission is
junk. Just for your information, a typical transmission will die within 1000 klm
if subjected to 300º F + heat. |
