UK Car Repair: Rolls Royce Auto gearbox, vacuum modulator, vacuum pipe

Question
I have a 1995 RR silver spirit 111 no modifications, which has travelled 55,000 miles. The gear changes are not seamless as I would expect. You can feel every up change particularly when accelerating hard.What are the most likely causes?

Answer
Under normal driving conditions it should be smooth. Full, throttle driving will make it somewhat more noticeable.  Your car has a vacuum modulator which regulates the change process.  The vacuum pipe, from the right side of the manifold, ends with a rubber hose at the transmission, it may be loose or disconnected. If not the modulator is adjustable for higher or lower pressure. As a matter of interest, harsh changes are actually better for the trans than soft ones. Much like a regular clutch, the faster it engages the less slippage there is.