Steering knuckle slipped on strut tube- Carrera 4

[Ericson38]

We are looking at a 2006 C4 Cab that has a blown out front left tire(sidewall-inside), a leaking left front radiator, and the left aluminum steering knuckle (kingpin on older cars) has slipped a few inches where it clamps on the bottom of the front strut. They are putting in a new rad, front strut, and tire on. Front rim is perfect, not bent, and balances fine, with no visible runout. Has anyone ever heard of the strut slipping on the attachment to the bottom of the strut ?

 

Thanks

 

[JFP in PA]

We are looking at a 2006 C4 Cab that has a blown out front left tire(sidewall-inside), a leaking left front radiator, and the left aluminum steering knuckle (kingpin on older cars) has slipped a few inches where it clamps on the bottom of the front strut. They are putting in a new rad, front strut, and tire on. Front rim is perfect, not bent, and balances fine, with no visible runout. Has anyone ever heard of the strut slipping on the attachment to the bottom of the strut ?

 

Thanks

 

Only when someone did something stupid.  This car sounds like it may have been run up on something as leaking radiators are often the result of something on that side suffering an impact, like running the car up on a parking space curb or a rock.

[Ericson38]

 

We are looking at a 2006 C4 Cab that has a blown out front left tire(sidewall-inside), a leaking left front radiator, and the left aluminum steering knuckle (kingpin on older cars) has slipped a few inches where it clamps on the bottom of the front strut. They are putting in a new rad, front strut, and tire on. Front rim is perfect, not bent, and balances fine, with no visible runout. Has anyone ever heard of the strut slipping on the attachment to the bottom of the strut ?

 

Thanks

 

Only when someone did something stupid.  This car sounds like it may have been run up on something as leaking radiators are often the result of something on that side suffering an impact, like running the car up on a parking space curb or a rock.

 

 

I could not find a single mention of this type of issue with the front suspension, and this is the 1st car we have gotten serious about, so was thinking, I can't have an issue on a potential car that is 'unheard of'. :eek:

 

At least on this 2006 C4, the way the knuckle clamps with a single large bolt around the bottom of the strut, rather thatn being bolted to it, seemed to suggest a purposed intent on relieving pressure under extraordinary compression (rates). Without this slip, I would think that the top of the strut may have but a bump on the front bonnet, via the top mount being super-extended.

 

The strange thing to me is that the rims of the front wheel are fine, and since these cars are tracked, maybe this is a built in safety release of pressure.under compression.

[JFP in PA]

 

 

We are looking at a 2006 C4 Cab that has a blown out front left tire(sidewall-inside), a leaking left front radiator, and the left aluminum steering knuckle (kingpin on older cars) has slipped a few inches where it clamps on the bottom of the front strut. They are putting in a new rad, front strut, and tire on. Front rim is perfect, not bent, and balances fine, with no visible runout. Has anyone ever heard of the strut slipping on the attachment to the bottom of the strut ?

 

Thanks

 

Only when someone did something stupid.  This car sounds like it may have been run up on something as leaking radiators are often the result of something on that side suffering an impact, like running the car up on a parking space curb or a rock.

 

 

 

The strange thing to me is that the rims of the front wheel are fine, and since these cars are tracked, maybe this is a built in safety release of pressure.under compression.

 

 

 

We have been servicing an repairing these cars for many years, and I have never hear or read about any kind of "safety release under compression" for this component, but we have seen people get overly creative when trying to drive them and end up over their heads and with an extensive repair bill.  And the lower strut clamping mounting method is commonly used on a lot of vehicles, not just Porsches.

 

If you are seriously considering this car, I would not buy it without having the car's four wheel alignment checked first, and perhaps even having it checked on a frame jig for straightness as well.

[Ericson38]

 

 

 

We are looking at a 2006 C4 Cab that has a blown out front left tire(sidewall-inside), a leaking left front radiator, and the left aluminum steering knuckle (kingpin on older cars) has slipped a few inches where it clamps on the bottom of the front strut. They are putting in a new rad, front strut, and tire on. Front rim is perfect, not bent, and balances fine, with no visible runout. Has anyone ever heard of the strut slipping on the attachment to the bottom of the strut ?

 

Thanks

 

Only when someone did something stupid.  This car sounds like it may have been run up on something as leaking radiators are often the result of something on that side suffering an impact, like running the car up on a parking space curb or a rock.

 

 

 

The strange thing to me is that the rims of the front wheel are fine, and since these cars are tracked, maybe this is a built in safety release of pressure.under compression.

 

 

 

We have been servicing an repairing these cars for many years, and I have never hear or read about any kind of "safety release under compression" for this component, but we have seen people get overly creative when trying to drive them and end up over their heads and with an extensive repair bill.  And the lower strut clamping mounting method is commonly used on a lot of vehicles, not just Porsches.

 

If you are seriously considering this car, I would not buy it without having the car's four wheel alignment checked first, and perhaps even having it checked on a frame jig for straightness as well.

 

I'll keep the topic updated when I get more information on it.

 

On this specific question, have you ever seen this slip between the knuckle and the lower end of the strut, on a Porsche ? Was it a 977 ? Does the C4 and C2 share the same fitment of the lower end of the strut into the al. knuckle ?

 

Thanks again.

[JFP in PA]

 

 

 

 

We are looking at a 2006 C4 Cab that has a blown out front left tire(sidewall-inside), a leaking left front radiator, and the left aluminum steering knuckle (kingpin on older cars) has slipped a few inches where it clamps on the bottom of the front strut. They are putting in a new rad, front strut, and tire on. Front rim is perfect, not bent, and balances fine, with no visible runout. Has anyone ever heard of the strut slipping on the attachment to the bottom of the strut ?

 

Thanks

 

Only when someone did something stupid.  This car sounds like it may have been run up on something as leaking radiators are often the result of something on that side suffering an impact, like running the car up on a parking space curb or a rock.

 

 

 

The strange thing to me is that the rims of the front wheel are fine, and since these cars are tracked, maybe this is a built in safety release of pressure.under compression.

 

 

 

We have been servicing an repairing these cars for many years, and I have never hear or read about any kind of "safety release under compression" for this component, but we have seen people get overly creative when trying to drive them and end up over their heads and with an extensive repair bill.  And the lower strut clamping mounting method is commonly used on a lot of vehicles, not just Porsches.

 

If you are seriously considering this car, I would not buy it without having the car's four wheel alignment checked first, and perhaps even having it checked on a frame jig for straightness as well.

 

I'll keep the topic updated when I get more information on it.

 

On this specific question, have you ever seen this slip between the knuckle and the lower end of the strut, on a Porsche ? Was it a 977 ? Does the C4 and C2 share the same fitment of the lower end of the strut into the al. knuckle ?

 

Thanks again.

 

 

Yes, but only in cases where there was abuse (the car hit something like a curb or pothole very hard; or someone had not reassembled the car correctly).  C2 and C4 cars use different front strut and wheel carrier assemblies, but  both have a similar method of how they are clamped in the wheel carriers.  If you have access to a Bentley service manual, there are complete diagrams and photos of both style assemblies.

[semicycler]

If the sway bar drop link bolt on top is loosened the knuckle will move on the strut.  It's common to see the knuckle slide a bit when upgrading the front sway bar or when installing adjustable drop links.  In your case check the sway bar and drop links for impact damage.

[Ericson38]

If the sway bar drop link bolt on top is loosened the knuckle will move on the strut.  It's common to see the knuckle slide a bit when upgrading the front sway bar or when installing adjustable drop links.  In your case check the sway bar and drop links for impact damage.

 

OK, I see what you are talking about, in this image, part (L) is the wheel carrier, and has slipped up on the strut.

 

http://www.elephantracing.com/suspension/diagram/996-997-suspension-navigator.htm

 

Being our first purchase, I was kind of amazed to see the wheel carrier had moved move up the strut body (1 inch), but also kind of thought it depends on clamping force, bolt torque, and I can also visualize that the car could be lowered this way (??). Is this an intentional safety release mechanism for track car type antics ? If I'm way off, please advise. JFP says abuse (I agree), but I don't think intentional.

 

I have a VW Westy Bently manual ('90 camper) and I take it they made 977 manuals too.

 

Thanks again.

Edited April 20, 2015 by Ericson38

[Ericson38]

Finally got the new strut on left front corner, and left radiator (vent line fitting broke), and new tire. Drove the car to the local INDY and frame checked great, but alignment was way off. Tech put all the alignments back at their mid points on the four corners and stated it didn't take much to get it aligned, from that point (laser 4 wheel alignment system-they do mostly Porsches and Miatas here. He said they don't all act like that, but the car is very straight. So if you ever hit a curb or pot hole hard enough to slip the front wheel carrier clamp on the strut, it doesn't mean the tub just got tweaked.