I have a 97 Ranger 4X4 extended cab, with an Eagle and airbags. It has always started to vibrate and shudder over 65mph. Just had it aligned and new ball joints on the front and thought that might allow me to do more than 65, but the shudder is still there over 65. It gets pretty bad over 70. So, I just drive around 65, but would like to go faster. My mechanic thinks it's just the weight on the truck. It goes along okay, but would sure be nice to do 75 on the interstate. Any ideas out there or similar experience?