I bought my Jeep in December, it's a 2006 SE 2.4L 6 speed, 3:73 gears. Right now with stock tires I can do 75-80mph easy with power in 6th gear. If I put 31" MT/R's on, will I still be able to use 6th with the stock gearing. This is a DD about 80 miles a day mostly highway. Thanks!