Does my 1985 mercedes benz 380 SL convertible run hot on the highway at 70 mph as the temp. Gauge maxes out at around 98C and varies down to about 90C to 95C. I just had the coolant and thermostat changed and the car still runs at these temperatures. The temp. Gauge I know "sticks" sometimes because I can pull back and release the break release and the needle drops back down some. I've been assured by my mercedes tech. That this is normal for my car and even in hot weather with the air on, the temp. Gauge might run over 100C.