[Ol'Jim]

I think what you are asking about, is called converter slippage. Which is perfectly normal. A torque converter does not lock up solid like a manual clutch, (except when it is a lockup converter, and all of the operating conditions have met the programmed parameters in the PCM). So, excluding the topic of lockup converters, any T.C. is actually a "fluid clutch", and by their nature, the more torque you put into it, the more it will slip. Which also multiplies the torque. Think of it this way: Say your engine has a powerband that makes peak torque at 4,000 RPM, and peak HP at 5,000 RPM. If your converter didn't allow the slippage to enable higher engine RPM at full throttle, your car would be a turd when trying to accelerate. Say you were in 3rd gear at 40 MPH, and your engine is at 2500 RPM, and you enter a highway on-ramp, and step on the gas to get up to speed. Your engine might only make half as much power at 2500 RPM as it does at 5,000. So your car would accelerate very slowly, and it would not allow you to use the full amount of power your engine is capable of making. But if your converter was extremely "loose", so that you were at 4 or 5,000 RPM while cruising at 1/4 throttle, your fuel mileage would suck, and trans fluid would get very hot. It is a compromise, which allows you to cruise and get decent mileage, but still accelerate when you need to. And if a converter didn't slip at all, ever, you could not sit at a red light in gear. It's job in that situation is to let the engine keep turning, while the transmission output shaft is stopped. This is a simplified explanation, I hope it helps. What you are seeing is normal.