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kerb damage - wierd camber angle

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I recently had an disagreement with a roundabout and ended up hitting and mounting kerb after the car slid. i lost the wheelarch liner as it caught the kerb and ripped out,, but the car still drove ok.  However as expected, The steering is now pulling under acceleration quite heavily to the left and braking to the right and is heavier than before. I assumed i'd knocked the tracking off but the wheel still steers straight ahead.  Upon closer inspection the nearside front wheel has a noticeable difference in camber angle (left wheel leaning in about a lot more than the right).  There is no sign of chassis twisting as all shut lines are normal, and no signs of unusual movement in the strut tower.  But upon checking, the wheel appears to be closed to the strut on the affected side.  I can't see any sign of a kink in the strut housing, and no sign of damage in the knuckle (only an initial look without the wheel off), but clearly something is amiss.

 

The kerb i hit was at about 30mph, but wasn't a square kerb, but the angled tyre (thankfully), and the impact caused a section of the rim protector on the tyre to separate from the tyre wall.  Clearly alignment needs sorting (a recent pothole managed to flatten the rim and blow out the tyre), but the camber angle is baffling me, particularly due to the wheel gap to the strut.

 

Anyone off me any suggestions?  The car is a 2009 Mondeo Mk4 hatchback.

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Bad luck with that kerb.....

 

Reads like the camber has moved negative ( wheel toward the car from the top ) the displacement is from the violent up-stroke ( camber curve ) resulting in two areas in your case.

 

1: The lower wishbone has bent at the neck/ ball joint. This type of damage you won't be able to see but a geometry will detect a change in the angle of the pin coming out of the ball joint. This angle is known as, KPI King Pin Inclination or SAI Steering Axis Inclination depending on the machine. The measurement is difficult to visualise. If the KPI/ SAI pin is vertical it will read as 0, As the pin declines the number gets higher, so if the wishbone is bent the NSF might read as 14 degrees 30 minutes but the OSF might read 10 degrees 30 minutes. Most manufactures don't offer a reading because the angle is purely for diagnostics.

 

 

2: The bottom of the strut fits into the cast hub which is angled at 90 degrees. When this is bent the cast will flake leaving a witness mark which should be easy to see once the wheel is off.

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Tell me about it....at least it wasn't a square kerb - otherwise I'd probably been looking at a snapped alloy, or worse!

 

Thanks for the great info Tony,  I did have another look last night at it and it does look like there has been some movement on the hub knuckle to strut point - although the movement is on the back of the strut (underneath the clamp), which I would have thought would make the wheel run further away from the strut than nearer!  judging my the damage and the fact i was breaking at the time of impact, that would add up as the bottom of the wheel would have taken the primary impact.  I can't feel any signs of stress cracking around the strut base, but I guess i will know more when I pull the wheel at the weekend. 

So, thinking about how the impact occurred, will the ball-joint have bent upwards or downwards? Annoying really as I only replaced both the strut and lower arm less than 18 months ago!

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The joint would bend upwards leaning the wheel inward from the top toward the car. The SAI normally increases so a higher number away from the vertical.

 

The hub if bent normally makes the cast lose material by flaking. Another area is on the damper at the point it fits in the hub although this is less common..

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Thanks Tony, guess i better prepare for an expensive weekend!

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Ideally a geometry image that includes the SAI/ KPI will speak volumes... If the SAI/ KPI's on the front read similar the logistically the bend would be at the cast hub. If the SAI/ KPI on the NSF has a greater number than the OSF then it suggests the wishbone. Remember the higher the SAI/ KPI's number the lower the pin is at the ball joint.

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