My 1996 Cadillac Seville won't shift into overdrive. Any suggestions???
When driving 45 mph or less the car operates at about 1800 rpm.
55 = 2100 rpm
65 = 2500 rpm
75 = 3100 rpm
The transmission starts to get hot at speeds above 55 mph. If I stay off the interstate the car runs perfectly. I just had a major tune up, other than the high operating speed and a slight increase in temperature (I constantly monitored the temp when driving for diagnostics) the car is running perfectly. The car has 117,000 miles. Also, this car lived in Alaska for the first 18 years of its life. I recently relocated to Florida, I'm pretty sure that my car does not like the hot temps!