We have always taken 191 North to 128, then East on 128 (beautiful drive) to I-75, East all the way to KC. Roads are good, shouldn't have any problem with a 40'. Take it slow going over the mountains and watch the fuel gauge - fill often.
128 out of Moab to I-70 East, should have no issues. It is a good climb up to the Eisenhower but it is built to interstate standards, so not too much of a problem. Pick a good time to pass through the Denver area and traffic should not be a problem. Kansas is just a long haul.
I agree, I-70 is not too bad. Just check your coolant before climbing up the pass from Dillon to the Eisenhower tunnel. It is a long, consistently steep hill that can stress out cooling systems. The other passes are not too bad, just gear down and use engine brakes on the downhill runs, when warned to do so. Take your time through Glennwood Canyon, very scenic, and the highway is one of those you will say "how did they build that"? Chris g. Westminster, CO.
There are 805.66 miles from Moab to Kansas City in west direction and 961 miles (1,546.58 kilometers) by car, following the I-70 route.The halfway point is Vona, CO. Kansas City and Moab are 14 hours 13 mins far apart, if you drive non-stop. Please note the time difference between Kansas City, MO and Moab, UT is 1 hour. For example, the current time in Kansas City is 10:20 pm, while the current time in Moab is 9:20 pm.