Cruise Control not working right - 95 Isuzu Rodeo 2WD
When cruise control switch is engaged at cruising speed (55 or so) on straight away road, it'll kick in for 10 seconds. Then it'll shift down to next gear as if I was going uphill. What might be the problem? Other, it drives good. It has 240,000 with good compression/good gas mileage (25mpg). Any assistance is appreciated.