# How to replace the front wishbone rear bush



## John-H (Jul 13, 2005)

*How to replace a front wishbone (TCA) rear bush*










This is the rear bush (3) of the front suspension TCA (Track Control Arm) or wishbone (1). These bushes don't pivot but instead tilt their axis as the TCA pivots up and down with the strut. This puts a tearing strain on the bonded rubber of the bush and eventually the centre tube of the bush, which is actually an alloy ball section, will separate and come loose. The TCA will then become sloppy and handling suffer.

Replacement usually involves removal of the TCA from the vehicle and separation of the lower strut ball joint which can be difficult. Undoing the three ball joint nuts is easier but will lose the tracking and camber adjustment. It's possible to carefully mark the joint and replace in the same position but it doesn't need to be far wrong to upset the tracking. It's also more work.

It is possible to replace the bush on the vehicle without removal of the TCA. This is done with a suitable puller which can be made from an M12 bolt nut and discs, rings and washers that press on the outer tube of the bush and clear the inner tube, so the rubber is not strained.

*Parts needed are:*

8N0 407 181 B - solid bush
N 102 622 02 - M12x1.5x70 shouldered bolt for rear TCA bush
N 015 081 6 - M12x1.5 shouldered nut for rear TCA bush bolt
N 904 840 04 - M12x1.5x82 shouldered bolt for front TCA bush

*Procedure:*

Loosen the bolts of the wheel to be removed and raise the car at both sides so the front wheels hang free to relieve the forces in the anti roll bar. Remove enough engine undershield screws to gain access to the front bush bolt (4) and remove the bolt. Hold the nut (6) with an 18 mm ring spanner and undo bolt (5) with an 18mm socket on a long swing handle.

The rear of the TCA can then be pulled out of engagement with the sub frame. The front bush just pivots in the sub frame. Do not pull the TCA completely away from the sub frame to avoid over extending the drive shaft spline joints. The rear of the TCA can be rested against the sub frame.










At this point either the old bush can be pressed up and out from below or it can be drilled cut and prized out




























Once removed the TCA will need cleaning with emery cloth or abrasive paper.










Once cleaned, a light application of grease will allow easier pressing in of the bush from above. The bush needs to be pressed in so the outer tube is flush with the top machined face of the TCA. Make sure the inner tube is clear and unstrained and all forces are brought to bear evenly on the outer tube of the bush. If the bush is pressed in unevenly, the outer tube can become partially collapsed and work loose in service.



















The TCA can then be pushed back into position and the new bolts and nut fitted. These are both stretch bolts and need tightening to *70 Nm + 90°* (1/4 turn). After torquing to 70 Nm the angle turn is best done by marking the bolt head and sub frame to check the 90° rotation rather than risk the socket slipping off and not being sure how far the stretch turn has been applied. The nut on the rear bush bolt will need carefully holding so it does not turn whilst tightening the bolt from below. The longer bolt (M 12 x 1.5 x 78mm) at the front bush position should be fully tightened with the vehicle standing on its wheels to ensure no residual twist in the bush which could reduce its service life.

Tracking can be checked by noting whether the steering wheel is still in the same straight ahead position when driving in a straight line. A wheel alignment will be required if this is not the case.

*Special tool details:*

The bush dimensions are (mm):

Bush outer tube diameter = 60
Bush outer tube height = 24.5
Bush centre tube height = 40.9
Bush centre tube required diameter = 25 (33 including rubber)



















*Parts required:*

M12 x 110 high tensile bolt
M12 full nut
M12 washer (two off)
Round steel cap 70 diameter x 10 with 13 diameter centre hole
Round spacer 70 diameter x 10 with 42 diameter centre hole (two off)
Square steel plate 70 x 70 x 10 with 13 diameter centre hole

To adapt the tool to press out the bush is more exacting mechanically as a tube must be pressed against the bush outer tube but clear the TCA casting. The outer diameter of this tube should be 59 mm and 30 mm deep. Similarly, a clearance recess to receive the bush must be slightly bigger than the bush outer tube but still sit firmly on the TCA casting. The bore of this tube should be 61 mm and at least 25 mm deep (as distorting the rubber is acceptable on removal). It would look something like this:


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## steveupton (Mar 23, 2010)

As usual, a very detailed and easy to follow guide, very interesting to see this job done with the TCA in situ, didn't think it could be done that way. Too late for me now as did mine with the TCA's removed.


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## TT DWN UNDER (Aug 29, 2007)

Wow..that little bush press is a winner, I had mine done at a garage and had to take the whole wishbone out..Nice one John


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## warrenstuart (Mar 3, 2010)

Excellent write up John as always [smiley=thumbsup.gif]

Good to see this done in situ and far less hassle than removing the whole TCA.
Do you have a list of bits that you made the puller out of please? I can see what it is more or less but i think this will be a job for the next MOT on my daughters 225 so a list of "tried and tested" parts for the puller would be nice 

Warren.


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## John-H (Jul 13, 2005)

I've added some detail about the press tool requirements. It's easier to make a tool to press in the bush than it is to press it out as the dimensions are more exacting.


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## brian1978 (Jul 10, 2013)

Brilliant guide, I've done mine now I used a vice a 4lb hammer a big socket and a lot of swearing to get mine in. Going to make that little press for the other side when it needs done, looks like an utter godsend.


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## warrenstuart (Mar 3, 2010)

John-H said:


> I've added some detail about the press tool requirements. It's easier to make a tool to press in the bush than it is to press it out as the dimensions are more exacting.


Thanks for adding the press tool detail [smiley=thumbsup.gif]

Warren.


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## Nem (Feb 14, 2005)

Great guide John 

One question, I'm assuming the front inner bush on the wishbone being quite flexible is what is allowing the rear to be moved out enough to gain access to replace it. With the Defcon mod installed and therefore a much smaller bush on that inner joint would there still be enough movement do you think? Or would having the Defcons fitted not make any difference?

Thanks.


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