I'm not knocking anyone on here but I have stock tires and the best I have seen on the DIC is 22.9 and that was all highway at 62 mph for 180 miles so to say you have oversize tires that weigh 55 lbs or more ( all LT tires do ) and I have stock ones that weigh 35 lbs and your still getting the same mileage and my DIC is always one mpg to the good ( high ) and the best I have ever done hand caluclated was 19.6 witch I am very happy with. But if there's a secret to getting 22 with big heavy tires please let me know I'll even pay you for it if it works