Fit new wishbone. Refitting is the reversal of removal as they say, with some extra notes... Again, holding the the shock out of the way place the wishbone in the rear subframe bracket first as it's easier, and important to keep the wishbone level, or as with removal, the rearward bush will twist and catch in the subframe bolt holes. Place the correct bush bolts in from the correct direction noted earlier with the new nuts and leave loose for now....
Fit the new steering knuckle pinch bolt and nut, if you have lemforder parts, this is a bit of a battle as it involves forcing the wishbone down and lining the the pin up at the right angle with the whole in the hub, note the grove in the steering knuckle pin, this is to allow the bolt to pass through and to stop the pin falling out if the nut comes loose. It must line up with the level of the bolt for it to fit correctly, or the bolt will not go in.
Now re fit the the drop link and torque all the bolts correctly, EXCEPT THE FRONT BUSH BOLT! LEAVE THIS LOOSE AND FOLLOW THE BUSH BOLT TIGHTENING PROCEDURE LISTED BELOW!
Lower balljoint to knuckle is 100nm/74lbs ft.
Anti-rollbar link rod to strut 65nm/48lbs ft.
Now do the passenger side, exactly the same except owners with hid lights will need to remove the sensor from wishbone to chasis. Take extreme car with these as they get fragile with age and are expensive to replace, in fact now is a good time to grease and carefully inspect it for seizing joints. Undo the torx bolt, wishbone bracket to sensor, be careful not to whack or damage the sensor while you work......and remove the rags used to block the subframe holes once both sides are done.
wishbone bolt tightening procedure.Vitally important to get this right to avoid early failure of the front wishbone bush. Repeat this procedure again should you fit new springs or lowered suspension.
Some pictures of why this is important and what will happen first of all, if not tightened correctly early failure will result.
This is result of emergency braking force causing toe out, meaning the front wishbone is pulled outboard compressing the bush on the inner edge, damage, by my finger, is not massively important but partly shows, along with the other pictures, why its important to change wishbones in pairs, uneven performance will result. If one side is new, this side will not behave the same under braking or react the same to the road surface.
Here the tears are self evident,
This is the rear bush on the wishbone and is not too bad but to give an idea, shows the start of failure, tear just starting
...and a further explanation.
Usual error is to tighten the bolts wheels hanging while the car is jacked. Simulated here, the vice takes the place of the tightened subframe bracket clamping the bush center spacer. Note the angle of the wishbone pointing down.
Here the angle of the wishbone is raised to simulate the ride height. ie with wheels loaded car on the floor. Note the bush center spacer has not moved and the bush rubber is stressed.
Now the bush is stressed even further, as the car corners and or hits a bump for example, the bush is stretched further than it was ever designed to.
Similar shot shows the bush rubber has torn through, hole clearly visible
Its interesting to note that the last two pictures show a difference in the wishbone bush center location in that the center spacer is not central in the bush when twisted, but in the last picture with the same torn bush in an unstressed position it returns to center. There is nothing to say that a torn bush will hold the road wheel in the correct position, in fact failed bushes are often blamed for a loss of set up causing extreme inside shoulder wear on the tyres. Similar condition to poorly set up camber on the shocks. Most garages are not aware the omega is adjustable for camber on the bottom shock mounts so camber setting is usually set far too aggressively causing similar tyre wear problems. Camber should be set to 1 degree 10mins.
So, important to tighten wishbone bolts correctly, as follows
The bolts should be tightened to 120nm, then angle tightened a further 30 degrees, then a further 15 degrees, with the wheels loaded in the correct ride height position, vauxhall recommend adding weight similar to that of the driver with a full tank of fuel when doing this to insure the bush center spacer is clamped by the subframe bracket in the least stressed position in the middle/average of its travel.
Like so in this simulated picture, this does not assume the ride height position gives a level wishbone