Ivylog wrote:
Too much air in new tires especially will give loose handling but if the pressures are around 100 psi then there's probably something else wrong.
340 HP will be a Cummins ISB 6.7L engine... a good LITTLE engine but less than 700 ft lbs of torque. A Cummins ISL (400-450 HP) 7.9L engine is limited to 1250 ft lbs as that's the max for the Allison 3000 tranny.
340 compared to 400 not a big increase, but 690 to 1250 is a huge difference.
Maybe in your coach.... I run 110 in the rear and 120 in the front AS RECOMMENDED by CC!