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Chip Hedrick

Broken Strut Tower Bolt. Safety Issue?

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This weekend I performed the so-called "grounding mod." Everything went great until I tightened the nuts on the two strut tower bolts on which I had attached grounding wires. I snapped off one of the three bolts on the passenger side strut tower.

 

Is it safe to drive around for a few thousand miles with one of the bolts broken off? I don't think there is any way to repair it short of removing the strut and replacing the strut mount.

 

By the way, to what torque should the nuts on the strut tower be tightened? The Haynes manual is unclear on this point.

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I can't answer your questions, but I've heard of this happening before. Those bolts take a very low torque I believe... Like only 20 or 25 ft-lbs. But don't quote me. I'm sure someone will know.

 

Commuter

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It "probably" will be ok, but you should replace it. You'll need a new top mount.....either just to swap it out, or to have a machine shop pull the bolt in the new one, to put in the old one....

 

The spec only says to torque to 14 ft/lbs......or that's what everyone says.

 

You don't need to tighten them super tight.

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Of course no one can tell you how long it will last, but from an engineering point of view, having an axis that something can now vibrate/move around is usually a recipe for disaster. That third bolt was preventing that. You now have a line instead of a tripod support. Any movement will be concentraed between the 2 remainig supports. Fix it soon.

 

 

Carl

1 Lucky Texan

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Here's the answer you don't want to hear: DO NOT drive anywhere with the car in this condition. It's not just your life and well being, but also the other people you share the roads with ;)

 

On the other hand, the bolts are that small because they don't have to work very hard, most of the time the car's weight holds the top of the strut against the tower. Only when the suspension expands (deep holes/jacking up) do the bolts really come into play. Oh, and they stop the strut support rotating along with the steering - the McPherson set-up relies on rotation about the strut "axle" for steering movement.

 

If it were my car, I would flatbed it home or to the mechanic and fix it. I'd hate to have the front suspension play a prank on me during a brake/turn-in/throttle open/throttle close/oversteer manouvre :brow:

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Thanks for the replies.

 

You've convinced me that I should replace the strut mount as soon as possible, but I'm not convinced that the broken bolt creates such a safety hazard that the car shouldn't be driven. (As one of the posts mentions, the greatest force is upwards against the strut tower, and the bolts likely don't play much role in controlling that). I'll just make certain not to engage in any high performance driving in the interim.

 

I figure if I go through the effort (or the expense of having someone else do it) of replacing the strut mount, I should replace the strut. And if I replace the RH front strut, I might as well replace all four (and their mounts and dust boots).

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Are you going to replace them with OEM? If so could you do me a favor and take a couple of measurements of the new ones before you install them.

 

-From the bottom to the top of the cone where the spring rests

-The length of the untensioned spring

 

email if you want hocrest@earthlink.net

 

Thanks

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You can drive the car with the stud missing. I wouldn't drive too far or too agressive though.

 

and yes, if you do replace the strut on the one....might as well do all the rest.

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Chip,

Thanks alot, the attached image is the dimension I'm looking for on the strut.

 

Also, is that measurment on the KYB the same. And what will the KYB's do to your ride height?

 

Thanks for your help.

post-16-136027584885_thumb.gif

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