Disco 2 noisy on acceleration

Discovery 2 TD5 Auto, 1999.
vibrating/rumbling when accelerating starts as soon as i touch the throttle and stop as soon as i take my foot off the pedal,
it has new front prop and just done a gearbox oil and filter service today, had an Ashcroft heavy duty torque converter fitted about 3000 miles ago, any help would be greatly appreciated.

Check the rotoflex at the rear

Also look at what has been most recently done.... check the tightness of the bolts on the front prop.

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