John deere clutch control valve

[Razorready]

Can anyone tell me what the symptoms of a bad valve is? My 6430 is sharp on the shuttle but ok on the foot pedal. If i fether the foot pedal in really slowly i can feel the tractor juddering as if its grabbing slightly was thinking of changeing the valve as ive had it calibrated which did help but i still dont think its rite.

 

[tweedale terrier]

Probably needs calibrated.

 

[Razorready]

Probably needs calibrated.

Yea ive already had it calibrated it did improve it