Extended Shackles..... vibrations?

[robmacca]

Guys.....

I've just installed some extended rear shackles in my D22 which lifted the rear end by around 40mm (800mm from bottom of rim to guard). I've spoken to some who have installed the extended shackles & then started to noticed a small vibration in the driveline at low speeds.

I can't be sure whether what I'm noticing was there b4 I installed the shackles or after or whether its all in my head, but what I "think" I'm noticing only happens in 2nd gear and only around 30>33kms/hr as per GPS and tends to decrease as the cars warms up (this I need to verify more though). This so called vibration is only fleeting and only minute as well and something that I'm not overly worried about, but I thought I would put it out there to find out if others with extended shackles have experienced anything like I've described.... ?



cheers....
Rob

 

[happy john]

Is it not to high? on standard rims mine is 760mm from bottom of rim to guard with a standard efs lift and no body lift Zordo told me any more and it would be above the limits and this is the problem faced apparently some sort of wedge fixes the issue what that is i am unsure mate best to ask him direct.

 

[robmacca]

Is it not to high? on standard rims mine is 760mm from bottom of rim to guard with a standard efs lift and no body lift Zordo told me any more and it would be above the limits and this is the problem faced apparently some sort of wedge fixes the issue what that is i am unsure mate best to ask him direct.

cheers for that..... I'm assuming the wedge is to help out with the Drive shaft angles and put the angle back to normal specs....

I don't have a BL in mine and the height was 760mm b4 installing the shackles and 792mm on the RHS and 805mm on the LHS after installing the shackles.

As I said, what I'm noticing is only felt in 2nd gear and at a speed between 30>35km/hr. Travel at that speed in any other gear and u don't feel/notice anything..... and what I'm feeling is only minute

 

[gazza414]

Its no different to adding xtra lift springs ?..why dont those guys have a vibration ?

 

[fourocker]

Lifted springs are manufactured with this taken into account, extended shackles on stock springs does not.
I had exactly the same or possibly worse when I put my shackles in, I think castor wedges (I've seen them on Superior Engineering's web site) are probably the best solution although I found my own by modifying the holes through the centre bearing mount frame and spacing up the centre bearing mount frame too, it turned out to simple enough but took a while to work out but my ute drives the same as before now.
I'll bet if you put a load of say 100 kg in the back it's probably fine because the axle then pulls away from the back of the transfer which alleviates the pressure pushing into it created by fitting extended shackles, this is how I worked out my solution, with a load on it was smooth as a farm truck could be.

 

[robmacca]

Lifted springs are manufactured with this taken into account, extended shackles on stock springs does not.
I had exactly the same or possibly worse when I put my shackles in, I think castor wedges (I've seen them on Superior Engineering's web site) are probably the best solution although I found my own by modifying the holes through the centre bearing mount frame and spacing up the centre bearing mount frame too, it turned out to simple enough but took a while to work out but my ute drives the same as before now.
I'll bet if you put a load of say 100 kg in the back it's probably fine because the axle then pulls away from the back of the transfer which alleviates the pressure pushing into it created by fitting extended shackles, this is how I worked out my solution, with a load on it was smooth as a farm truck could be.

How does that work as the front spring mount is fixed and prevents the diff from moving forward?
There is the twist factor & this is where the wedges would probably help....

 

[fourocker]

The shackle effectively lowers the rear end of the spring using the front eye as a pivot, this means the diff/axle swings in an arc toward the front of the car.

 

[robmacca]

Just made up some wedges and installed them..... Seems to have decreased the vibration, but I might need to adjust them & I reckon it will sort out all vibrations......


rob

 

[robmacca]

Just re-adjusted the wedges and re-inserted them so they are in the Front of the diff..... all vibrations are gone.... thank goodness....


Now, just got to find out where the clunking coming from up front when offroading. It's definitely not the steering stops has it happens when driving straight ahead..... I've looked under there and cannot see any metal rub marks at all..... got me stumped

Just made up some wedges and installed them..... Seems to have decreased the vibration, but I might need to adjust them & I reckon it will sort out all vibrations......


rob

 

[fourocker]

Great to hear the vibes are sorted !