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Ground Control rear shock mount failure

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Old 10-27-2008, 08:55 PM
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MM951
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Default Ground Control rear shock mount failure

I'm driving along at 75mph on a perfectly level, straight road and then...... BANG. I look in the mirrors and see pieces of my BRAND NEW 285 p-zero (replaced after they rubbed because of my orginal shocks) flying everywhere.

I stopped and the rear driver wheel is 1/2 covered by the rear 1/4 panel and the lower shock mount snapped flush with the trailling arm

wtf?? I can't see how it would snap like this on one side and not the other ??? Both were installed properly and the other side is still perfect... needless to say I'm SUPER PISSED... I paid $800 for the rear coilovers and $330 for a new rear tire... now I have to get another tire and another shock mount (or should I even trust it..)

Then when the tow truck was dropping my car off at the house they scraped the **** out of the rear diffuser/bumper. and he was putting the car on the truck he was about to loop the strap around the front swaybar!!

oh yeah.. and this was the first day I was able actually drive/use my car to go to school/work etc .. and now this
Old 10-27-2008, 08:56 PM
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Lorax
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Yikes, and you arent even running very stiff springs
Old 10-27-2008, 09:02 PM
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Chads996
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Call Jay at GC before going nuts. I'm sure he will help you find out the problem.

C.
Old 10-27-2008, 09:40 PM
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marky522
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Are you using the proper lower bolt?http://cgi.ebay.com/ebaymotors/ws/eB...m=150305943880 Or did you ust mount the coilover directly to the lower point like the old shocks?

Mark
Old 10-27-2008, 09:55 PM
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MM951
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ground control lower mounts are a copy of racers edge lower mounts irrc..

Old 10-27-2008, 09:57 PM
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Yabo
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Man, you are murphy's law incarnate huh?
Old 10-27-2008, 10:07 PM
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MM951
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I know its ridiculous......and of course it happened a few minutes after I was thinking how great the car is to drive and how all this BS I've gone through with this car was worth it. I wonder how great life will be when my luck changes.
Old 10-27-2008, 10:20 PM
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Chads996
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There is an important bit of torque on that bolt that is needed to properly "set" the bolt in place. It's something crazy like 150lbs. It tensions the bolt in place. If it is not set, the bolt loses strength. I remember reading something about it. Again, check in with Jay at GC.

C.
Old 10-27-2008, 10:25 PM
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flosho
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Pictures man?
Old 10-27-2008, 11:43 PM
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VOoDOoGTX
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ill give you tree fidy for the car.

im just gonna offer people money everytime somthing breaks.
Old 10-28-2008, 01:57 AM
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MM951
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just want to make it clear I'm not bashing GC.. more just frustrated that this happened...paid a lot of money for the coilovers now another $300 tire, $100 tow (that damaged my car) and having to deal with a flush broken stud that was tensioned at 96 ftlbs (as per the factory manual) on top of the nightmare this car has been is just really gettin to me.

the good news is the car runs great.. I just had a slightly high idle (need to replace idle screw to reset idle) and a little more finessing with the arc2 for higher loads until I can get my maxtronic back.
Old 10-28-2008, 09:45 AM
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MAGK944
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Be nice to see a pic of this, I am running these also so am a bit concerned as I tightened the bottom nut to the same torque as you. They look bullet-proof and well made, so were exactly did they fail and what springs # were you running?
Old 10-28-2008, 10:07 AM
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Chads996
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Originally Posted by Mike Markota
...tensioned at 96 ftlbs (as per the factory manual)...
I think that is the problem. Even the Racer's Edge installation manual for their version states you need to tension it above that. I truly think that may be the problem. Keep in mind, that is not a factory part. Therefore, the factory torque may very well not be accurate.

Talk with GC.

C.
Old 10-28-2008, 10:09 AM
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Chads996
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Here is the copy from the Racer's Edge installation guide:

"INSTALLATION INSTRUCTIONS FOR LOWER SHOCK MOUNT ADAPTER

Congratulations!!! You have made an excellent choice in the purchase of your lower shock mount adapter from Racer’s Edge. Racer’s Edge components are precisely machined from MIL spec material and heat treated to achieve optimum strength. It is critical the user of these products understands that these components only achieve full load carrying capability when the adapter is torqued to the specifications listed below. We recommend rechecking of these torque values every so often as to maintain a level of confidence that the piece is installed properly. It is also a good idea to “mark” the position of the adapter and bolt with paint so any loosening of the pieces would be more easily noticed. We recommend that the instructions below are followed exactly. We also recommended that a qualified technician install these components and that the directions be read in their entirety before work begins.

NOTE: This adapter is for use with shocks which have a ½” ID spherical bearing on the end with a width no greater than .5”. If the spherical bearing bore is greater than .5” wide, as is used on some Bilstein and other shocks, a longer adapter bolt must be used. Contact Racer’s Edge before installation if you have any questions concerning this issue.

1. Before installing the adapter, make sure that the mounting surface area of the trailing arm is flat, with no high spots. If there are high spots within the area where the adapter will contact the trailing arm, carefully remove these with a file. Be careful not to create any low spots. Your goal is to create a flat mounting surface for the adapter to seat against. In most cases there will be no preparation work required.

2. Install the adapter into the rear trailing arm and torque to 150 ft-lbs. It is critical that this value be achieved by use of a torque wrench and not just “by feel”.

3. Slid the conical safety retaining washer onto the bolt, with the flat side against the head of the bolt, and then slip the ½” bolt though the eye of shocks lower spherical bearing.

4. Apply a suitable amount of anti-seize compound to the threads of the ½” bolt to help prevent water ingress. Do not put any in the bore of the adapter as, if too much was used, it may prevent the proper seating of the bolt.

5. Insert this ½” bolt into the adapter and tighten. Torque this ½” bolt to 52 ft-lbs.

6. It is recommended that the bolt be safety wired in place."
Old 10-28-2008, 10:20 AM
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MAGK944
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150 ftlb, mine are nowhere near that! I didn't have a deep enough socket to fit on that adapter so I used a wrench. It would be nice to have been told that by GC, seeing that racers edge make such a big deal on this "critical" torque. Be interested to see what they have to say.

Thanks Chad, good info.


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