This may have no direct relevance to the cruise control, but based on your numbers it sounds like your car doesn't downshift to third. It only goes to fourth gear. If it hit third gear, the rpm would exceed 4,000 rpm at 110kph (69 mph). It is very likely the first jump from 2,200 rpm to 2,600 rpm was the torque converter unlocking. Even though the rpm increased by 400, it was still in fifth gear. It didn't downshift yet. However the jump from 2,600 rpm to 3,000 rpm at 110kph sounds like a downshift from fifth gear to fourth gear. (I base that on the mathematics of the gear ratios.) You might find that to be good news. It seems like your transmission is not bouncing around that much at all. It is only dropping one gear.Thx for the responses. I'm talking about moderate hills, like going over an overpass. I'll be in cruise at 110kph at 2200rpm and it instantly goes to 3000rpm. Feels like the kickdown is a lot more sensitive in cruise control. Engine is allowed to work a lot more out of cruise before a downshift occurs and out of cruise it'll go to 4th(2600rpm) and not directly to 3rd. This is with an unloaded car.
Does anyone know if the cruise control is adjustable? I've had manuals before and the inclines I'm talking about wouldn't be long or steep enough to require a downshift.