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I come from China,I am a Buick Envision User,And I find that GM applied a new structure on lower control arm,It named "split-type lower control arm bushing".
Since 2014 ,"split-type bushing" applied on multiple models of GM,Such as Buick Envision,Buick LaCrosse2017,Chevrolet Malibu2016 and 2017.
"split-type bushing" is mainly composed of front little bolt,inner sleeve,rear little bolt,vulcanized rubber,outer sleeve.It is applied on lower control arm and be installed on frame.
"split-type bushing" easy to plastic deformation under low velocity impact!This is a design deficiency of product!Must be Recall!:frown2:
 

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It looks like the control arm mounting broke. Not very common but it does happen from corrosion from salt applied to roads during the winter time in North America. It can happen from hitting an object or a pothole.

I jump the rail road tracks near work sometimes and have unloaded the front end but nothing broke.
 

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I can answer your question

It looks like the control arm mounting broke. Not very common but it does happen from corrosion from salt applied to roads during the winter time in North America. It can happen from hitting an object or a pothole.

I jump the rail road tracks near work sometimes and have unloaded the front end but nothing broke.
Because , in most cases,front shock absorber support motor vehicle absorb impact.
But split-type bushings mechanical strength shortage!It is easy to plastic deformation.(As the material is deformed beyond the strain that elastic deformation persists, the stress is no longer proportional to strain, and permanent, nonrecoverable, or plastic deformation occurs. )
The inner sleeve is hollow and metal material is very thin.
 

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It looks like the control arm mounting broke. Not very common but it does happen from corrosion from salt applied to roads during the winter time in North America. It can happen from hitting an object or a pothole.

I jump the rail road tracks near work sometimes and have unloaded the front end but nothing broke.
Split-type Bushing is a unsafe structure!Since 2014, lower control arm falls off led to a series of accidents!
 

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You will face same problem ,Because interference fit structure is not strong!Once inner sleeve plastic deformation,it will become dangerous.Will led to lower control arm falls off!
 

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I come from China,I am a Buick Envision User,And I find that GM applied a new structure on lower control arm,It named "split-type lower control arm bushing".
Since 2014 ,"split-type bushing" applied on multiple models of GM,Such as Buick Envision,Buick LaCrosse2017,Chevrolet Malibu2016 and 2017.
"split-type bushing" is mainly composed of front little bolt,inner sleeve,rear little bolt,vulcanized rubber,outer sleeve.It is applied on lower control arm and be installed on frame.
"split-type bushing" easy to plastic deformation under low velocity impact!This is a design deficiency of product!Must be Recall!:frown2:
About 5-10 KM speed,when Front wheel touch stone or other wheel ,split-type bushings would plastic deformation ,even falls off!
 

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It looks like the control arm mounting broke. Not very common but it does happen from corrosion from salt applied to roads during the winter time in North America. It can happen from hitting an object or a pothole.

I jump the rail road tracks near work sometimes and have unloaded the front end but nothing broke.
A standardized stress test ,What's clear is that sofar,split-type bushing is structurally weak!
A solid steel bolt is the right choice!
 

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What is really clear is that your testing method is flawed. The split-type bushing was designed to used on a control arm that has other mounting points and support.

For a through test, mount the control arm on the vehicle then stress test it.

Besides, the fender is dented which means this vehicle was in an accident and components replaced before considered road worthy.
 

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What is really clear is that your testing method is flawed. The split-type bushing was designed to used on a control arm that has other mounting points and support.

For a through test, mount the control arm on the vehicle then stress test it.

Besides, the fender is dented which means this vehicle was in an accident and components replaced before considered road worthy.
The lower control arm is installed on a carframe in the test:you can see it!and to simulate the strength!From the test,we can find before lower control arm deformation,bushing's sleeve first plastic deformation!
Why?Because,inner sleeve show it is mechanical strength shortage!
I told you a truth:In August 2015,in homepage of China's patent offices,We find a patent of bushing for SGM(GM),in the patent ,GM recognize that split-type bushing is potential safety hazard for lower contrl arm!So them change the design! And design a new bushing!It is applied on XT5 later!It is named the monocoque bushing for lower control arm!
You can see attachments!
 

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What is really clear is that your testing method is flawed. The split-type bushing was designed to used on a control arm that has other mounting points and support.

For a through test, mount the control arm on the vehicle then stress test it.

Besides, the fender is dented which means this vehicle was in an accident and components replaced before considered road worthy.
You can see picture of lower control arm for Cadillac XT5
 

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What is really clear is that your testing method is flawed. The split-type bushing was designed to used on a control arm that has other mounting points and support.

For a through test, mount the control arm on the vehicle then stress test it.

Besides, the fender is dented which means this vehicle was in an accident and components replaced before considered road worthy.
You can see below video,In video,show a Envision's lower control arm closed to falls off!Less than 10 km,just Brush touch the wheels at the stairs.

 

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But doesn't the Chinese Envision uses a different suspension setup than the American Envision?
Chinese Envision uses the macpherson front suspension,and American Envision uses enhancement macpherson front suspension,but all use same front bushing on lower control arm.Please see attaments picture.

picutre 1 is american Envision lower control arm and picture 2 is a Chinese Envision lower control arm.
You can see same architecture of bushing!So same problem with us!
 

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What is really clear is that your testing method is flawed. The split-type bushing was designed to used on a control arm that has other mounting points and support.

For a through test, mount the control arm on the vehicle then stress test it.

Besides, the fender is dented which means this vehicle was in an accident and components replaced before considered road worthy.
Tell you a case:A Benz C200 low speed 10 km,it's vehicle wheel got slightly scratched a other Buick Envison's right wheel,C200 is ok,but Envision's right lower control arm falls off!See Picture.
 
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