Originally Posted by Henry Rifle
OK, guys, you may be overthinking this.
Do you want to know the temperature of the fluid in the trans, or impute it from the temp of the fluid coming back from the cooler? Suppose you have a really, really good cooler, and all you see is 160* fluid in the return line. OK, looks good. However, that cooler is giving you a 40-50* drop, and your trans fluid is really over 200*. You're fat and happy until your trans burns up. And knowing you've got a temp drop over the cooler, if you see 200 degrees going into the trans you know you're in trouble.
Why would you want to know whether hot fluid was going into the trans? If hot fluid is going in, it's surely going to be hotter coming out, because there is minimal cooling inside the trans. . MY point Exactly!
An automatic transmission - especially one with an overdrive - can flash excessive heat in a very short time. And, the temp IN the trans is what makes or breaks it. I want the best info at the potential point of damage.
Your mileage . . . or temperature . . . may vary. :LOL: