GERRY - Kinda off topic for bull dozers, but "ALL" IH trucks rode rough. Seems that IH used to like to design trucks with very tall stacks of short leaf springs for both frt & rear suspension. Once the leaves got rusty and didn't slide on each other any more they rode like there were NO springs at all.
I rode "shotgun" many thousands of miles in IH CO-190's with Dad hauling livestock back in the late 50's & early/mid 1960's. They were a cab-forward tilt-cab truck, the driver & pass. seats were right over the steer tires, the doors pivoted from the "A" pillar, in other words.... You would be the FIRST person on the scene of an accident. You felt every little ripple in the pavement, and as one old timer put it, you could tell if a Dime was heads up or tails up when you drove over it.
The old Red Diamond, or RD-450 gas in-line 6's were no power-house engine, but IH sure made a LOT of them. The guy Dad was driving for then later upgraded to a pair of Emeryville's, a Cummins 220-powered twin screw and a Cummins 185-powered single axle. They were bigger, faster, burned less fuel, but rode every bit if not more rougher than the CO-190's.