Method of controlling a transmission clutch

A method of controlling a clutch comprising:

• during a drive cycle, estimating, based on a model, a set of delays between initiating engagement of the clutch and changes in a torque capacity to pressure relationship;
• during a first clutch engagement, measuring the set of delays;
• updating a set of model parameters based on differences between the estimated delays and the measured delays;
• and
• during a subsequent engagement of the clutch, commanding a pressure to the clutch based on the updated set of model parameters such that at least one delay in the set of delays is reduced.

A method of controlling a transmission comprising:

• during a first positive torque upshift event,
• i) commanding an oncoming clutch pressure such that a piston of an oncoming clutch is stroked after a first delay, and
• ii) after the first delay, reducing an off-going clutch pressure to zero while maintaining a constant ratio of an input speed to an output speed;
• and
• during a next engagement of the oncoming clutch, commanding the oncoming clutch pressure such that the piston of the oncoming clutch is stroked after a second delay less than the first delay.