Juddering

Just bought a 306 D turbo `95. i recently changed 5 spoke spiral
wheels over to some XSI wheels on jack + axel stands under chassis
rail, ever since i have done this, i have been getting major juddering
from what i believe to be middle/rear of car under quite firm braking,
the wheels are not fouling anywhere and i have prooved my point
putting the old wheels back on, still juddery!. Now the shockers
seemed clunky and were found faulty once removed so i put some gas
shocks on, the ride is alot nicer now but the judders are still there,
ive tested obvious signs like exhaust rattle, had the drums off (shoes
ok + operate fine) checked bushes etc, no play/wear anywhere. i have
just raised the rear of car up and clicked handbrake up few notches
and span rear wheels, there seemed tight spots and light spots
spinning round the wheel, on both sides. Maybe some drum distortion?
but i am not convinced this is the problem...how could this just
suddenly happen?

 

Does the car have rear disk brakes? I had bad juddering on my 406 and it
was down to warped front brake disks. It happened very suddenly with no
warning. If you have rear disk brakes that could be the cause, or it could
still be the front ones because the judder is not necessarily emanating from
where it seems to.

 

Its got drums on rear, today i had the drums off and glazed the drum +
shoe surface, it made a vast differance and has made the noise + feel
less violent, my front brakes are screwed but i have discs + pads on
order for tomorrow, so i have added drums and rear bearings to that
order, hope this solves my problem, i will let you know

 

My fingers are crossed for you.

Keith

 

Right, later on that day the juddering got worse, started knocking
when i hit pot holes etc...so i knew it wasnt the brakes, managed to
get it up on our flat bed ramp at work whilst someone bounced on the
rear, its one of the rubber supports for the rear axle that has gone,
i have bought all four mounts to replace, any ideas the best way to go
about changing them? a side at a time or lower the whole axle and do
them all and raise it all in place, i have the equipment to do it just
not the time, so the quickest way to do it would be nice/ any
techniques etc.
Thanks