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Suspension Replaced front lower control arms and springs....suspension won't compress?

  • Thread starter Thread starter Gs1987GT
  • Start date Start date Jul 1, 2020

Gs1987GT

Active Member
Sep 25, 2019
484
170
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MidAtlantic
Jul 1, 2020
#1
  • Jul 1, 2020
  • #1
Gents, good morning,

I installed the right side new lower control arm and new coil spring last evening and it wont compress at all, even with the full weight of the car on it.

I've never had that issue before. I'm using LMRs lower control arm set and husky RC8602 springs. These springs are slightly taller than stock (15.38 vs 15.2) and are a heavier rated spring, 1820 lbs vs 1740. I figured hauling my big behind around and maybe long term more resistance to sagging, a little heavier spring was a good idea, but now I'm not so sure.

I'm 100% sure its installed correctly in the upper and lower spring perches, I just looked at it again this morning with fresh eyes.

I wouldn't think the marginally heavier/taller spring would cause this issue, but with the full weight of the car down and a Jack under that right side arm, I can't see any compression at all, or very minimal. To check myself, I can compress the old/original left side spring using the same technique, I have not touched that side yet.

I'm thinking at this point, it has to be because the spring is too heavy (rated) and that 80lb difference between it and the OEM spec spring must be the issue. I find that hard to believe, with the minimal heavier rating and height, but at this point, with only the strut orignial strut connected (I was going to change that next) I can't come up with anything else. I can't see what else could have it in a bind like that. I couldn't compress it hardly at all when the rear control arm bolts were still loose either. I wanted to preload the arms before tightening the bolts and that's when I saw the issue at hand.

Any thoughts would be appreciated before I take it back apart again.

Thanks
Greg
 

OldManRiver

Active Member
Feb 14, 2015
238
131
53
Central Wisconsin
Jul 1, 2020
#2
  • Jul 1, 2020
  • #2
Man those are some serious springs,I thought the stock rear spring rates were in the 200-300 lb. range and the fronts 400-500 lb.
 

Gs1987GT

Active Member
Sep 25, 2019
484
170
53
MidAtlantic
Jul 1, 2020
#3
  • Jul 1, 2020
  • #3
It may be that is how they are listed. That's their load carrying capacity, not spring rate.

I do believe after looking at it again they are too heavy. The car lifts off my lift and they still don't compress. It's not the strut either, I just checked that.

Time to come back apart again and order the correct oem spec replacements.

That's what I get for trying to re-engineer stuff! Lol
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,260
17,945
224
Massachusetts
Jul 1, 2020
#4
  • Jul 1, 2020
  • #4
Assuming the control arm itself isn’t binding, it’s the spring
 

Gs1987GT

Active Member
Sep 25, 2019
484
170
53
MidAtlantic
Jul 1, 2020
#5
  • Jul 1, 2020
  • #5
Thanks. The control arm is not binding, that was checked. I ordered a set of OE spec stock springs for my application. Wish me luck ! Not a fun job.
 
Reactions: General karthief

Steel1

Mustang Master
Aug 18, 2017
1,419
639
143
Connecticut
Jul 1, 2020
#6
  • Jul 1, 2020
  • #6
I've done front springs a couple of times and always felt better unbolting the back of the control arm
from the K member.
Just a matter of getting a jack under there , unbolting the control arm and lowering the spring out the back side.
 
Reactions: Gs1987GT

Gs1987GT

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Sep 25, 2019
484
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Jul 1, 2020
#7
  • Jul 1, 2020
  • #7
Steel1 said:
I've done front springs a couple of times and always felt better unbolting the back of the control arm
from the K member.
Just a matter of getting a jack under there , unbolting the control arm and lowering the spring out the back side.
Click to expand...

Yes, I did a lot of research on it before I took it apart and that's exactly how I did it. It wasn't too bad, but I had my sons helping position the two Jack's and raise as I worked the control arm into position. If I was doing it solo it would be much more difficult.

I'm returning the husky springs and ordered the OE replacement this time. After I got it back apart, I put the rear control arm bolts back in and the lower control arm moved as it should. Smooth and no binding, so it had to be the spring. I'd have never thought the small difference between the initial ones I ordered and the OEM spec could cause an issue like that, but I was wrong.

Another lesson learned.
 
Reactions: Cheapskate207

Gs1987GT

Active Member
Sep 25, 2019
484
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MidAtlantic
Jul 4, 2020
#8
  • Jul 4, 2020
  • #8
Completed the front end rebuild today guys. Stock ride height restored, no more tire rubbing. The problem was the springs. The 15.4" relaxed height/1820 lb rated springs were too heavy to compress for my car. The oe spec is 1740lb load rating, 15.2" relaxed height, those worked good.

Now if maximim motor sports ever gets around to shipping me the rear axle bushings I ordered on 6/16 and LMR sends me the BBK upper control arm the set they sent me was missing (one failed attempt and counting), I can do the rear suspension, then move onto the clutch and rear main crank seal and full exhaust job!
 
Reactions: General karthief

2000xp8

SN Certified Technician
Aug 8, 2003
8,029
1,621
194
NJ
Jul 6, 2020
#9
  • Jul 6, 2020
  • #9
Maximum motorsports is seriously backed up.
I called them since i'm waiting on some parts.
High demand with everyone at home working on their cars and supply chain problems.
Honestly with California's current condition, I wouldn't be looking out the window every day for the UPS guy...
 

Gs1987GT

Active Member
Sep 25, 2019
484
170
53
MidAtlantic
Jul 7, 2020
#10
  • Jul 7, 2020
  • #10
Lol...agreed. I did get notice that my bushings are being shipped, so good news there
 

manicmechanic007

5 Year Member
Sep 26, 2017
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Roy, Utah
Jul 18, 2021
#11
  • Jul 18, 2021
  • #11
Neutralize the suspension. It is in a Ford NVH manual. Means pull vehicle onto a pit where you can loosen all the suspension bolts while the car sits at its normal ride height. Might as well neutralize the exhaust too while you are down there.. I used to do it a lot to Broncos and Expeditions. It paid about 2.8 hours to do both. Do it and your car will drive like a dream. A common suspension mistake is to bolt it all together tight without being at the proper ride height (guilty) sometimes do it on purpose a little
 
Reactions: JD1964

JD1964

there is enough sticking out to grab on to
15 Year Member
Jun 28, 2013
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Jul 18, 2021
#12
  • Jul 18, 2021
  • #12
Would that procedure also work on an alignment lift?
 

2000xp8

SN Certified Technician
Aug 8, 2003
8,029
1,621
194
NJ
Jul 18, 2021
#13
  • Jul 18, 2021
  • #13
John Dirks Jr said:
Would that procedure also work on an alignment lift?
Click to expand...
It should work on anything as long as it's sitting on all 4 wheels.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,260
17,945
224
Massachusetts
Jul 18, 2021
#14
  • Jul 18, 2021
  • #14
You could do it on crib blocking as well. You just need weight on the wheels
 
Reactions: manicmechanic007

manicmechanic007

5 Year Member
Sep 26, 2017
2,536
714
143
Roy, Utah
Jul 18, 2021
#15
  • Jul 18, 2021
  • #15
John Dirks Jr said:
Would that procedure also work on an alignment lift?
Click to expand...
Yes
 

manicmechanic007

5 Year Member
Sep 26, 2017
2,536
714
143
Roy, Utah
Jul 18, 2021
#16
  • Jul 18, 2021
  • #16
Any blocking will do. Lately I have had to fix a few Mercedes suspensions. I just use 2x8 pieces to block the wheels up
 

Wayne Waldrep

Before I post a pic, do you have one of yours?
20+ Year Stangneter
Apr 14, 2003
1,338
659
143
Cuba, AL
Jul 26, 2021
#17
  • Jul 26, 2021
  • #17
manicmechanic007 said:
Neutralize the suspension. It is in a Ford NVH manual. Means pull vehicle onto a pit where you can loosen all the suspension bolts while the car sits at its normal ride height. Might as well neutralize the exhaust too while you are down there.. I used to do it a lot to Broncos and Expeditions. It paid about 2.8 hours to do both. Do it and your car will drive like a dream. A common suspension mistake is to bolt it all together tight without being at the proper ride height (guilty) sometimes do it on purpose a little
Click to expand...
Good post!
This and proper sub frame connector installation is too often overlooked or just not done because the person didn't know. Pays to do things correctly the first time.....even if it takes a little longer.
 
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