Changing the wishbones (front lower axle arms) and subframe support bracket

Jack up the  car and support on stands- I put the car on Halfords axle stands on the first pin position. Higher would be better as you do need a bit of room underneath to wield a breaker bar or torque wrench! I currently have 4 post ramp-envy!

If you look at the Autodoc vid for changing Micra wishbones, you will see that its merely a 10 min job... yeah and the rest! Expect to take around an hour at least depending on how much trouble there is in releasing everything. The vid also shows a Micra 3 which is marginally different as it lacks the front sub frame support brackets. 

The first step is to remove the wheel and then loosen the ball joint pinch bolt. You will need a 16mm spanner to hold the nut and an impact wrench with an extension bar.

Tools for the pinch bolt
The nut comes undone relatively easily but it cab be a pig to remove the bolt once the nut is off. Use penetrating oil, refit the nut and hammer it out... you can see the rust that sticks it in. I found it helps if you used the impact wrench on the bolt head and hammer the nut end at the same time.
Pinch bolt removed- obviously rusty. I cleaned it up before refitting.

Pinch bolt out

The ball joint can then be loosened by hammering a long drift down from above beside the steering knuckle.

Slip the drift down alternately each side of the knuckle and hammer it next to the ball joint. Its a compromise between having a long enough drift to clear the steering knuckle and short enough to let you wield the hammer above without hitting the wheel arch.


It took a while but it did eventually start to come out. I found none of my ball joint separators would fit although the fork type probably would. I don't have one of those because it always damages the ball joint boot- not that this is a concern when you're changing it anyway!
Ball joint loosened
Pull the arm down to separate the joint completely and then remove the two rear bolts. Note BOTH of these are done up very tight (100-110 Nm) so you will need to loosen them with a breaker bar before unzipping them with an impact wrench. Hold the nut with a flat ring spanner. The rear bolt is 19mm and the front 18mm

Holding the upper nut with a flat ring spanner (top centre) and loosening the bolt with an impact wrench from below


Undoing the front bolt will also release the front sub-frame mounting bracket. I don't think this is a problem because the sub-frame is still held in by the other three bolts, but in case it dropped I supported it with a trolley jack and a wooden pack.
Supporting the sub-frame prior to removing the front bolt. Note the front sub-frame supporting bracket attached by the same long bolt and the top vertical fastening.
Having removed the two inner bolts, the wishbone pulled out really easily. (note here, the second side was more awkward and needed persuasion with a lever to come out from the rear mounting)
Wishbone removed.
Front bolt coming out.
Having learnt from my experience with the shocks I compared the new wishbone to the old. I bought Meyhle arms and the match seems good.
Comparison of old and new. Note that the old wishbone has a red plastic guard that covers the end of the ball joint rubber. I removed it, and cleaned it for installation on the new ball joint.
Cleaned up red protective washer ready to fit to new wishbone.
Here I found some really good news- the ball joint on the old wishbone was clearly worn, it was loose and floppy and I could easily detect the shaft popping in and out if I pulled it. It was so obvious I have to say I'm surprised that two garages missed it. As one was the garage that sold me the car and the other was in the same town (and familiar with the car) I am left to wonder if this was collusion designed to get me to put me off the job until the car was out of guarantee.  Hopefully this will solve at least some of my rattling problems- possibly the biggest part of it.

I had previously noted the the sub-frame support bracket on this side (right/drivers side) was pretty nasty although no movement wear was apparently detectable. The bush looks in poor condition and I intend to change it. The bracket is released by removing the upper bolt which feeds into a captive weld nut somewhere above.
Sub-frame support bracket upper bolt
The bolt is a long one with a tapered tip but it removes fairly easily. I found this was possibly not as tight as it should be because I could remove it with the impact wrench alone- I didn't need the breaker bar.


Long bolt with taper tip from the upper bracket mount
Removing the bracket is a bit awkward and it helps to release the splash guard by popping out this plastic rivet.
Plastic rivet holding the rear of the splash guard inside the wheel arch

Sub-frame mounting bracket



Once removed the poor condition of the bracket could be seen.... the rubber is deteriorating and there was rust inside. What was also seen was that once again suppliers have sent me the wrong part! Although I ordered a right-hand bracket, the bracket I received was clearly a left-hand version!!! I've ordered the new part; complete brackets are about £35 and new bushes  £19 for the pair.  I ordered the complete unit but I will have a go at repairing the bracket later on just to see how tricky it is. This left me with no choice: if I'm to progress today I will need to refit this dodgy bracket and replace it later. I re-inserted the bracket and held it loosely  by the top bolt. To fit the new wishbone insert the rear mounting first and loosely retain it with the bolt and nut.

You can then lever the arm so that the front mounting slips into its place in the sub-frame. This can be awkward- on my old Escort it was virtually impossible, but in this case I found it straightforward.
Front mounting inserted into subframe
Insert the long bolt from the front of the car to pass through both the bottom of the bracket and the wishbone bush and tighten it loosely
Bend the ball joint to align the spigot with the hole in the steering knuckle, fit the red protective shield and insert the balljoint into the knuckle. Look along the pinch bolt hole to make sure that the ball joint enters far enough so that the groove in the spigot aligns with the bore of the hole to open it out for the bolt.

Ball joint entering steering knuckle, check bolt hole is clear.

Tap the ball joint into place and insert the pinch bolt.

I don't think you these bolts should be tightened until the suspension is under load so I placed a block of wood on the trolley jack and jacked up under the ball joint to take the weight of the car and pre-load the suspension. I could then torque the pinch bolt to 65 Nm, the rear  arm mounting bolt to 110Nm and the front to 100Nm. I also torqued the bracket top bolt

Front of new wishbone torqued in

Rear of new wishbone.
Refit the wheel and lower the car. I will need to revisit the bracket later but for the time being I progressed to the other side (ball joint not worn, rear mounting bush harder to extract) and swapped the wishbone in a similar manner.

New Febi right hand sub-frame support bracket installed.


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