V9 spec c
front Helical LSD according to Rallispec data (I thought it was suretrac), rear platted, dccd

going on highway, and almost lost control - steering wheel began shaking soooo bad I could hardly hold it, initially it felt like I have a figure 8 in my front wheels (and they are not perferctly straight, but I balanced them a week ago)
this already happened a week ago when I was driving from Toronto, but it went away after 20 kms

sounds coming from diff (center or front) like something is slipping pretty bad
and at some point it makes it impossible to turn

I just went under the car and checked axles, they are fine, no play, nothing is torn

changed front to rear wheels

started it, had diff in unlocked mode and went for a little drive.... going straight is fine, turning - little noises coming (as usual, because of a bigger preload for spec c diffs)

then I set it to first lock mode (still green settings) and then middle, tried to turn and BANG CLANG CLANK! and almost impossible to turn again and noises of slippage

I have changed the tranny fluid 1k ago (scotty's cocktail)
put my summers couple of days ago, did allignment and wheel balancing

So what am I going to change? :(


here's an update... for anyone who cares :(
jacked all wheels in the air,
open diff - 4th gear, no noises.... turn wheels - no noises
locked diff - 4th gear, no noises... turn wheels - Clank!Clank!Clank!!!>.. :(

went under the car while my friend was in the car, seems like the sounds are coming from front diff

about 13k kms on the driveline

what is the rear ratio is it a 3.9. didyou try disconnecting the dccd controller to see if it was that because it sounds to me like something is wrong with that.

yes, 3.9
I don't see a point of disconnecting the DCCD though... it would behave just like if I ran it in fully open mode

Ok well when you diff is open no noises your front and rear diffs are still working. then you lock your dccd and the problems start. it sounds to me like either a wireing problem or center diff problem.

even when all 4 wheels are in the air and there is no load on them?

also the sounds were coming directly from front diff... I thought it was axles/CV joints at first :(

besides, it still clunks when turning even with unlocked center diff
sometimes even when I turn the wheel slightly while cruising I have these sounds
and when push gas, steering wheel begins to shake, goes away when I let go gas and go to neutral

so you do get the noises when the diff is open before you stated that you didnt.
did you wire up your dccd yourself and what one are you using if it is factory then there is alot of things that could be wrong.

it was always there, just not loud
now I can hear it good, and I don't have to turn that much

my DCCD is wired using rallispec harness, so I am confident in that

both outer CV joint were bad, finally replaced them - problem gone (hopefully for a while :p )