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A week or two ago I noticed a distinct knocking from my rear :wink: anyway having checked around the only thing I could find was that the lower bush in the P/X side shock was pretty much passed it. At the time could not find anything else amiss. Fast forward two weeks newly repainted springs/NOS shocks installed things still did not seem right. So re-checking I found (overlooked the first time) the TAB bolt loose, seems the thread had striped on the bolt. Fortunately I had some new ones in stock for another project but I thought it timely to post up this picture and remind everyone how important these bolts are for your car. Especially as we have a lot of new cars and owners around at the moment. This particular one had only been on the car for around 3000 miles/3 years. Lasted about the same time as my new clutch master cylinder that has also failed :roll:
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Chris
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Hi Chris
Could you PM who supplied this bolt??
Did you replace it yourself? Could it have been over-torqued (for example when you had the shims done)?? This is not wear and tear, or the normal type of failure from this component, right?
Cheers. Quite worrying!
andy
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Quote:Did you replace it yourself? Could it have been over-torqued
Yes I did three years ago when I put this car back on the road. I have done a few sets over the years and this is the first one thats gone like this, I'm guessing it was just a bad one, rather than bad fitting over from being over torqued. Just thought it's a good time to re-highlite these with all the new cars that have been brought in over the last few years.
Chris
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It's unlikely the bolt was over-torqued, because the torque setting defined in the manual of 55ft-lbs (or thereabouts, it's not onhand to check) is way lower than that recommended for s standard M12 join.
The stock bolts are 10.9 but a quick google shows that for a 12.9 the recommended torque is 100ft-lbs
http://www.hi-tensilebolt.com.au/Torque ... etric.html
NB this should still be well within the UTS of the bolt and the capabilities of the threads.
It looks more like a damaged nut, or one with some crap in the threads was forced on. This will then result in the wrong tension in the joint even if torqued to the correct value.
I have geomet-coated 12.9 Hex-head trailing arm bolts in stock.
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Quote:The stock bolts are 10.9 but
In this case yes it was indeed an OE stock 10.9, if there was crap in in the nut who knows, either way I should have known better than to replace it without checking what had been sent out. Fortunately no harm done the posting was more to remind everyone of the dangers of these.
Chris
