broken lower A arm mounts

[jschwartz]

I finally broke the rear lower A arm mounting plates clean off. I've been inspecting them regularly after hearing about problems on this site, and they've been bent for some time. Never had any visible cracks before.
Jeff S

[UltimaCH]

Ouh, bad news. Hope you didn't have any other problems (accident, etc.).

[Steve_D]

Jeff
Without wanting this taken the wrong way I'm glad it happened to you.

As the owner putting more power through the chassis and associated running gear than anyone else it should happen to you first.
If it had happened to another car it would have pointed to a more widespread issue for all of us.

If anyone is putting all their power to regular use then the Factory mount mod should be used.
No doubt Jeff's new mounts will be in a completely different league.

As above, hope nothing else happened in the breakage.

Steve

[Stig]

Ermmm.. if they were bent for some time, why didn't you replace them before they failed?

[spatz]

I understand that the mounts are the ones that are welded to the chassis and they broke off there ?
They look a little fragile to me too, still this is the first time I read about it and If I remember
right this is where the factory recommends using the big washer. So must be the piece that takes the biggest stress
and with Jeff doing quarter miles with his car...........

[GreenV8S]

jschwartz said:

they've been bent for some time.

If they folded sideways like the pictuires shown here a few months ago they will have been work hardened and more prone to failure - if they've been straightened that would make them a lot weaker. But surely you wouldn't continue to drive the car after the suspension mounts bent, until they'd been replaced and strengthened to stop it happening again?

[GTRCLIVE]

Thats it then perhaps it's time to change that OLD chassis now then Jeff....

[jschwartz]

Stig said:

Ermmm.. if they were bent for some time, why didn't you replace them before they failed?

Exactly.
They bent the first month I drove the car back in April 2003 with the 500 hp engine. 55,000 miles ago. Everyone denied there was a problem back then. I inspected them regularly for cracks since then. The point of posting this is to warn others, once they're bent there is no warning when failure occurs. I'm really lucky it happened at low speed as I was entering the park of my shop. I was just about to do a high speed rip through the country before it was stored away for winter. There's little chance I could have kept it on the road.

[k wright]

GTRCLIVE said:

Thats it then perhaps it's time to change that OLD chassis now then Jeff....

I'm thinking that he'll opt for a less massive solution.

[Stig]

jschwartz said:

Stig said:

Ermmm.. if they were bent for some time, why didn't you replace them before they failed?

Exactly.
They bent the first month I drove the car back in April 2003 with the 500 hp engine. 55,000 miles ago. Everyone denied there was a problem back then. I inspected them regularly for cracks since then. The point of posting this is to warn others, once they're bent there is no warning when failure occurs. I'm really lucky it happened at low speed as I was entering the park of my shop. I was just about to do a high speed rip through the country before it was stored away for winter. There's little chance I could have kept it on the road.

Jeff - I'm confused. Are you saying that you knew that they were bent, but continued to drive it without rectifying the problem?

Did they bend as a result of normal use, or from a hard dyno pull?

[deadscoob]

Not sure how to interpret this.

Once they bend they can go at any time

or

Once they bend, they can last for 6 years if you do 55,000 miles and have 1000hp

?

[spatz]

ok what is the fix ? anything from the factory or just take them all off and replace with stronger hinges ?

[GTRCLIVE]

Reffer to previous answer....

[Steve_D]

spatz said:

ok what is the fix ? anything from the factory or just take them all off and replace with stronger hinges ?

Have a look in the Factory Updates thread (Sticky).

Steve

[spatz]

I assume you mean those



Are these a bolt on to the existing ones reinforcing them ? Or must be welded on and used
instead ?
Is it wise to put them right away before bending occurs ?
sorry for the stupid questions.

Edited by spatz on Thursday 15th October 08:49

[Steve_D]

spatz said:

I assume you mean those



Are these a bolt on to the existing ones reinforcing them ? Or must be welded on and used
instead ?
Is it wise to put them right away before bending occurs ?
sorry for the stupid questions.

Edited by spatz on Thursday 15th October 08:49

They just sit over the existing mounts so no welding required.

If you believe you will be using all of your available power then perhaps fitting them would be a good move.
I have done 16K miles without bending the mounts and accept the predictable comments that I have not been trying hard enough. However, Jeff bent his then continued for 50K miles so your choice really.

Steve