Loose Rear-end Sensation (especially when accelerating)

[Bluemustang]

Really appreciate the feedback and suggestions!

Control arms are Ford Performance, I do have a set of Steeda ones with longer ball joints (but took these off sometime ago, did nsoftot like how the steering would get stuck when fully turned).

As for "bushings clocked/indexed" I don't entirely know what this means, and when I told the tech to make sure this was done when installing the springs, it seemed like I was speaking a different language. I would like to know more about this.

As for "negative camber is much less now up front", what should we have it set to ?

Clocking or indexing the bushings mean to reorient them to their new position. When you change the ride height from stock it changes the bushings preload. Basically it's not sitting in its ideal position to function properly. When doing lowering springs you MUST set the car at ride height with all 4 wheels on the ground and loosen the suspension pivot points (basically wherever there's a rubber bushing) so it can settle into the right position and then torque to spec.

Since you've lowered the car, you need more camber, especially in the front to handle optimally and more for aggressive cornering. Once you lower the car, you're outside the factory specs now. -0.5 camber is not acceptable. You need at least -1.5 front -1.25 rear imo for the street. Search for Kelly BMR alignment spec. The camber has nothing to do with your steering play though. That's different.

On the bushing clocking- there is a diagram showing exactly where the pivot points are. It is floating around here somewhere. Failing to clock the bushings properly can lead to erratic handling, reduced confidence and even bushing failure over time.

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[JayHij]

And I'm getting ready to install them and was under the impression that the play would be gone after. Hhmm.

Have you replaced any of the control arms up front? Did you just replace the bumpsteers or did you buy the Steeda kit that comes with the lateral links?

So a while ago, I use to have the steeda control arms. Did not like the feel of them, so switched the out the FP ones.

Clocking or indexing the bushings mean to reorient them to their new position. When you change the ride height from stock it changes the bushings preload. Basically it's not sitting in its ideal position to function properly. When doing lowering springs you MUST set the car at ride height with all 4 wheels on the ground and loosen the suspension pivot points (basically wherever there's a rubber bushing) so it can settle into the right position and then torque to spec.

Since you've lowered the car, you need more camber, especially in the front to handle optimally and more for aggressive cornering. Once you lower the car, you're outside the factory specs now. -0.5 camber is not acceptable. You need at least -1.5 front -1.25 rear imo for the street. Search for Kelly BMR alignment spec. The camber has nothing to do with your steering play though. That's different.

On the bushing clocking- there is a diagram showing exactly where the pivot points are. It is floating around here somewhere. Failing to clock the bushings properly can lead to erratic handling, reduced confidence and even bushing failure over time.

Thanks for the explanation on clocking/indexing the bushings. Am I hoping someone who is experience in lowering vehicles would be privy to that. I will figure out way of double checking that.

As for the Alignment, this is my current read out:

Looks like the fronts really need to be adjusted. I think this is the first time I am going to try out (adjust the alignment). I showed him the BMR specs, and he told me he thought that was too aggressive. Im going go back to him.

 

[boB]

This one didn't have a bump steer kit, did ok: https://www.caranddriver.com/featur...-gt-performance-package-2-lightning-lap-2018/

 

[JayHij]

Clocking or indexing the bushings mean to reorient them to their new position. When you change the ride height from stock it changes the bushings preload. Basically it's not sitting in its ideal position to function properly. When doing lowering springs you MUST set the car at ride height with all 4 wheels on the ground and loosen the suspension pivot points (basically wherever there's a rubber bushing) so it can settle into the right position and then torque to spec.

Since you've lowered the car, you need more camber, especially in the front to handle optimally and more for aggressive cornering. Once you lower the car, you're outside the factory specs now. -0.5 camber is not acceptable. You need at least -1.5 front -1.25 rear imo for the street. Search for Kelly BMR alignment spec. The camber has nothing to do with your steering play though. That's different.

On the bushing clocking- there is a diagram showing exactly where the pivot points are. It is floating around here somewhere. Failing to clock the bushings properly can lead to erratic handling, reduced confidence and even bushing failure over time.

So took it in for an Alignment, got it much closer to the BMR recommended specs. Steering has gotten a lot better. There is still some play, but not as bad. Now whats bothering me even more, is this (having a hard time explaining) soft/bouncy feel of the car. I just don't feel like I have full control.

And I think it has to do with my Yellow Koni's (both Shocks and Struts). During the Spring install, both sets were adjusted to the softest setting. I think this will be the next thing I try to adjust...

Anyone have a recommended settings for the Koni Yellows (street/daily driving) ?

 

[NightmareMoon]

So took it in for an Alignment, got it much closer to the BMR recommended specs. Steering has gotten a lot better. There is still some play, but not as bad. Now whats bothering me even more, is this (having a hard time explaining) soft/bouncy feel of the car. I just don't feel like I have full control.

And I think it has to do with my Yellow Koni's (both Shocks and Struts). During the Spring install, both sets were adjusted to the softest setting. I think this will be the next thing I try to adjust...

Anyone have a recommended settings for the Koni Yellows (street/daily driving) ?

Konis are ~10 quarter turns of adjustment (2.5 full rotations = 10 quarter turns), so I use tenths/quarter turns to count settings.

I liked 3/10 (3 quarter turns out of 10 from full soft) in the front and 1.5/10 (1 quarter turn and an eighth) in the rear for a comfortable yet controlled street ride on the Koni yellows. Full soft is too soft for sure and you'll get some bounce/float.

If you want something more sporty, try 5/10 Front and 3.5/10 Rear, that was my middle "sport" setting. in a competition setting I'd go as high as 7 or 8/10 Front and 6.5/10 Rear. Full stiff was too stiff with stock springs IMHO, but YMMV.

 

[JKL1031]

ymmv?

 

[JayHij]

ymmv?

"Your Mileage May Vary" basically like saying "may be different in your experience"

Konis are ~10 quarter turns of adjustment (2.5 full rotations = 10 quarter turns), so I use tenths/quarter turns to count settings.

I liked 3/10 (3 quarter turns out of 10 from full soft) in the front and 1.5/10 (1 quarter turn and an eighth) in the rear for a comfortable yet controlled street ride on the Koni yellows. Full soft is too soft for sure and you'll get some bounce/float.

If you want something more sporty, try 5/10 Front and 3.5/10 Rear, that was my middle "sport" setting. in a competition setting I'd go as high as 7 or 8/10 Front and 6.5/10 Rear. Full stiff was too stiff with stock springs IMHO, but YMMV.

Really appreciate the Feedback, I'm going to try messing with it, and see where I like it. For the rears, was it easy/hard to do? Can you do it from home?

 

[NightmareMoon]

"Your Mileage May Vary" basically like saying "may be different in your experience"



Really appreciate the Feedback, I'm going to try messing with it, and see where I like it. For the rears, was it easy/hard to do? Can you do it from home?

You just need to jack up each rear side by like 2-4 inches to squeeze an arm over the top of the rear tire. Its not a big deal, but I certainly don’t change settings every time I get in the car.

 

[SgdriskillGT]

Same thing was happening to my GT, felt like a boat under acceleration. Back end jerking laterally back and forth.

Ford replaced a rear knuckle and issue is completely resolved!

 

[JKL1031]

Just discovered my RR LH wheel bearing has play. Make sure you guys check the rear hubs with the parking brake disengaged.

Hopefully this should do it for me..

 

[JayHij]

Same thing was happening to my GT, felt like a boat under acceleration. Back end jerking laterally back and forth.

Ford replaced a rear knuckle and issue is completely resolved!

Do you know which rear knuckle specifically ?

Konis are ~10 quarter turns of adjustment (2.5 full rotations = 10 quarter turns), so I use tenths/quarter turns to count settings.

I liked 3/10 (3 quarter turns out of 10 from full soft) in the front and 1.5/10 (1 quarter turn and an eighth) in the rear for a comfortable yet controlled street ride on the Koni yellows. Full soft is too soft for sure and you'll get some bounce/float.

If you want something more sporty, try 5/10 Front and 3.5/10 Rear, that was my middle "sport" setting. in a competition setting I'd go as high as 7 or 8/10 Front and 6.5/10 Rear. Full stiff was too stiff with stock springs IMHO, but YMMV.

Will the car need to be re-aligned after adjusting the shocks/struts?

 

[JKL1031]

Do you know which rear knuckle specifically ?



Will the car need to be re-aligned after adjusting the shocks/struts?

Nooo

 

[JayHij]

I have the same rear end wobble under hard acceleration, feels like a boat / the rear toe is out of wack and pulling the car left then right.

After a week at a dealership, they said the issue is one of the knuckles is falling apart... They are replacing it tomorrow.

I’ll let you know if that fixes it. Crossing my fingers.

Any updates on this ?

I am still feeling some looseness in the rear, even after the alignment, and adjusting both the shock and struts, It's better, but something still feels off.

What is the easiest way to tell if i having any issues wither either the knuckles or wheel bearings ?

It has also been very frustrating that any shop I have been to thus far (over 5) have no clue what re-indexing or clocking the bushings mean after lowering the vehicle (I even tried explaining to them as it was explained to me and they still give me this dumb look).

Anybody know of a good shop in SoCal that KNOWS our vehicles ?

 

[JKL1031]

jack up the rear. pry the top of your wheel with your risks leveraged at your knees and kinda push with your knees. u shudnt feel any place. make sure parking brake is not engaged.

 

[NightmareMoon]

Yeah, get it up in the air, parking brake off, get your arms around the wheel and try to rock it front to back or top to bottom. You'll know pretty quickly if it is out.

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