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

Gs87GT

Active Member
Sep 25, 2019
238
77
38
Penn's Woods
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
 
  • Sponsors(?)


Gs87GT

Active Member
Sep 25, 2019
238
77
38
Penn's Woods
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
 

Steel1

Mustang Master
Aug 18, 2017
1,186
545
143
51
Connecticut
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.
 
  • Like
Reactions: Gs87GT

Gs87GT

Active Member
Sep 25, 2019
238
77
38
Penn's Woods
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.

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.
 
  • Like
Reactions: Cheapskate207

Gs87GT

Active Member
Sep 25, 2019
238
77
38
Penn's Woods
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!
 
  • Like
Reactions: General karthief

2000xp8

SN Certified Technician
Aug 8, 2003
7,006
1,095
194
NJ
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...