I've only just skimmed through this thread, mostly as I get frustrated at hearing about.... such and such at DUM Offroad Super store said they fit suspension to Defenders all the time bluh bluh... and the end result it handles, rides, shudders, "they cant get the alignment right", "you need to trim the front with some u-buet off set bluh bluhs" like a complete dog.
Its taken me many years to get suspension right on Defenders, often because each time one comes in the customers requirements are different. I do use Terrafirma suspension, I'm not saying their products are the be all and end all, but I generally find their specifications are what the glossy sales info says and mostly because I've worked out the short falls over the years.
Anyway, my point...
The de-acceleration vibration is the from prop shaft as its working outside of its designed angle, keep in mind though not all Defenders will suffer this. I use a heavy duty front prop shaft for a Discovery 2 and fit a Discovery 2 front output flange.
British Parts of Utah
Discovery Front Driveshaft Drive Shaft TVB000110
Regards
Daz

