2007 GT Rear suspension concern?

[Alatalo]

BMR’s pics for reference:




It's little bit difficult to see in the pictures, but I do get the impression your LH side LCA relocation bracket is twisted in relation to the rear axle due to not being mounted with all of the bolts...? Again, hard to see without extreme zoom. But it looks like the top part of your LH side bracket sits more forward in relation to the big, rusty hole just in front of the panhard bar attachment...? Which obviously indicates especially the LH side of the rear axle sits more forward in relation to the LCA.

The obvious proposal would be to re-mount both LCA relocation brackets according to the instructions, with the correct tightening procedure as well as the correct tightening torque. When you're at it - pay attention to the LCA's themselves. They are usually not symmetrical. There is a front and rear side. There is a LH and RH side. Don't get them mixed up, or you will have severe binding problems.

Assuming the car has not been crashed and twisted, a rear wheel that sits too far forward or too far back in the wheel well can be only because of an incorrect length LCA or incorrectly manufactured or mounted LCA relocation brackets. The rear wheel will indeed move a small amount back and forth throughout the suspension stroke. But a broken rear spring would be detected because of a massive height difference from side to side rather than the rear wheel moving a few millimeters back or forth.

Same thing with the panhard bar - it has a big effect on the side-to-side positioning of the rear axle, but next to no effect on the longitudinal positioning of the rear axle.

 

[Dino Dino Bambino]

There are two problems that are immediately obvious when you look at the pics:

1. The relocation brackets aren't mounted the same way on both sides. I'll post pictures of mine for comparison.

2. The LCA is mounted on a higher relocation bracket bolt hole on the left side.

 

[Samos3]

Did u read the detailed instructions ? The axle weight gets tossed on both sides. THREE bolts are used to bolt the LCA. Two on the side and one on the back end. Then the 4th bolt is used to bolt the LCA to the LCA relocate bracket, using one of the 3 holes available.

https://www.bmrsuspension.com/?page=products&productid=170

click on the 3rd pix, then blow it up. u can clearly see all FOUR bolts in the pix. The kit comes with 4 x long bolts...and 2 x real short bolts....PER side. They have to be installed in the correct sequence, and also torqued down correctly. Just follow the instructions.

To be fair, there are lots of pics on the web of relocation brackets without the upper bolts. So many that I wasn't sure if it's needed in all applications.

 

[Pentalab]

To be fair, there are lots of pics on the web of relocation brackets without the upper bolts. So many that I wasn't sure if it's needed in all applications.

With only one mounting bolt per side vs the 3 per side it should have..... The entire LCA bracket is fee to pivot.

 

[Samos3]

With only one mounting bolt per side vs the 3 per side it should have..... The entire LCA bracket is fee to pivot.

Can't tell in the pics if the rear upper bolts are in place. Doesn't the panhard rod bolt go thru one of the brackets?
Even with that bolt in, the stress on the tab going up where it is welded to the main part of the bracket could be working on flexing it without the upper side to side bolt.

If there is no upper rear bolt on the other tab (without the panhard rod to secure it), then the bracket could be pivoting. Creating the clunking noise, misaligned axle, and twisting the upper control arm.

I think the pics I'm finding are unfinished installations, although some seem to have everything else back in place and no upper side to side bolt. Discounting the pics where the axle has dampening weights that hide that part of the bracket.

 

[JC SSP]

There is more going on here…

Even before installing the relocation brackets his tire & rearend were out of alignment.

 

[Samos3]

There is more going on here…

Even before installing the relocation brackets his tire & rearend were out of alignment.

That's what I recall, too. The BMR stuff is an attempt to fix the initial problem?

 

[JC SSP]

Correct but I have a feeling there is more going on here…

Some one had mentioned collapsed spring or some other suspension issue…

 

[Midlife Crises]

View attachment 111860View attachment 111861

All the bolts in place. You can even see the little spacer used on the top bolt.

 

[BM08]

I was reading the installment what are dampening weights mines didn’t come with thoses

 

[BM08]

I’m pretty sure I saw those 2 bolts I should have them on my toolbox I was so confused when I got them and the video didn’t explain to me those bolts

 

[JC SSP]

bmr 2005 mustang rear suspension - Bing

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[GriffX]

Sad that BMR doesn't use automotive bolts. Simply looks unprofessional.
And they should offer a 2 hole option, the ground clearance is not big.

 

[Midlife Crises]

Sad that BMR doesn't use automotive bolts. Simply looks unprofessional.
And they should offer a 2 hole option, the ground clearance is not big.

I have read of more than one person cutting and grinding the lower hole away. The top hole works for me so I just ignore the others. Can’t see them from the drivers seat.

 

[whitmanink]

Sad that BMR doesn't use automotive bolts. Simply looks unprofessional.
And they should offer a 2 hole option, the ground clearance is not big.

they are 10.9 grade?
thats plenty strong?
or were you hoping for a dull blk bolt to show the grade?

 

[BM08]

There is more going on here…

Even before installing the relocation brackets his tire & rearend were out of alignment.

Yes you’re right after I swapped suspension parts and put tech touring lowering spring it started to give problems that I’ve been trying to figure the issue out

 

[Alatalo]

Yes you’re right after I swapped suspension parts and put tech touring lowering spring it started to give problems that I’ve been trying to figure the issue out

So this longitudinal positioning problem of the rear wheel was there BEFORE swapping LCA’s and LCA relocation brackets…?

A rear spring does not move the rear wheel forward or backwards more than a few millimeters unless it’s completely extended or collapsed. If this would be the case, the first thing you would notice is the car leaning sideways.

 

[BM08]

So this longitudinal positioning problem of the rear wheel was there BEFORE swapping LCA’s and LCA relocation brackets…?

A rear spring does not move the rear wheel forward or backwards more than a few millimeters unless it’s completely extended or collapsed. If this would be the case, the first thing you would notice is the car leaning sideways.

This issue began after I change the LCA AND UCA

 

[GriffX]

they are 10.9 grade?
thats plenty strong?
or were you hoping for a dull blk bolt to show the grade?

Zinc lamellar coated flange bolts. Better torque control and longer lasting rust protection.

The ride high is where the weight on the wheel is equal to the force of the spring (plus the spring base height)

 

[Alatalo]

This issue began after I change the LCA AND UCA

So, then the problem is for sure related to one of those.

If you look at pictures of really any S197 Mustang - no matter how much it has been lowered - you will notice all rear wheels are pretty centered in the longitudinal direction of the wheel well opening. This does not change with a noticeable amount unless there is a cock-up with the LCA length or the LCA mounts.

Go through everything again, making sure to follow the correct mounting procedure. Check the lengths of the LCA’s and the UCA and compare them to stock. Pay attention to their orientation as they are not symmetrical.