08 957 ctt. Question is does anyone know what goes on in these motors around 3000rpm? I have a pronounced vibration from the motor around this rpm. I can feel it in park and neutral so don't believe it's driveline related. Very pronounced when driving semi aggressive as it transmits to drivetrain. No codes in durametric and don't think it's fuel related. Any ideas?

 

How do your engine mounts look?

 

I wondered if it could be mounts too. I've replaced upper torque arm. Have new motor mounts and transmission mount sitting in a box in garage waiting on me to drop truck off at Indy to replace. Just haven't had time yet. Would be pretty sweet if mounts cure it.