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rear control problems

  • Thread starter Thread starter 306lx
  • Start date Start date Apr 13, 2005
3

306lx

Member
Mar 31, 2005
44
0
6
bakersfield, ca
Apr 13, 2005
#1
  • Apr 13, 2005
  • #1
i just installed UPR's non-adjustable upper/lower rear control arms on my 93 lx. to say the least i am not at all happy with these. i went from being able to almost drop the clutch at 3000 rpm on the street and bog, to not even being able to slip the clutch at 1000 rpm without blowing the tires off. i even notice a little wheel hop with a small burn out to clean the tires off, even with the recommendation from UPR that i would no longer need the quad shocks. anyway, before i go off spouting about a bad product i want to make sure there are no hidden tricks to installing control arms. it seemed pretty basic to me? any thoughts or recommendations? thanks guys.

by the way i am running a 26x11.5 m&h DOT slick.
 
J

jerryD

Founding Member
Mar 16, 2000
1,061
0
37
Gladstone, MO
Apr 13, 2005
#2
  • Apr 13, 2005
  • #2
did you torque the arms down with the weight of the car on it?
 

Ranchero5.0

The Voice of Reason
Jan 1, 1999
5,306
0
76
Hagerstown MD
Apr 13, 2005
#3
  • Apr 13, 2005
  • #3
MAC combo I did on a customers car locked the rear up, sound like what you're up against too. Also check that the rear shock isn't locking up on the shocks dust boot.

Jamie
 
3

306lx

Member
Mar 31, 2005
44
0
6
bakersfield, ca
Apr 13, 2005
#4
  • Apr 13, 2005
  • #4
thanks for the reply guys- no instructions came with the control arms so i just tighten the arms down pretty snug. i bought all new hardware with steel lock nuts so i wouldnt have any problems with them backing off. i tightened everything with no weight on the axle as the car was on jackstands. i didnt think that would be an issue because i thought no matter how tight the bolts where they would still be able to move in the bushings. also what do you mean by the rear end locking up and how do i fix this, our local track is open this friday and i was hoping to improve my ET
 

89MustangGX

I have nothing productive to add!
Jul 3, 2001
10,262
1
0
Mill Creek, WA
Apr 13, 2005
#5
  • Apr 13, 2005
  • #5
Jack the car up and loosen the bolts again -- you will probably hear a loud POP as the control arms unbind.

You need to have the jackstands under the axle when you tighten them, they are binding now and that's probably why you're having problems.
 
3

306lx

Member
Mar 31, 2005
44
0
6
bakersfield, ca
Apr 14, 2005
#6
  • Apr 14, 2005
  • #6
i was told that by having the car lowered with non-adjustable uppers that i just have way too much pinion angle. i guess lowering it adds about 1-2 neg. degrees then the arms add about the same? i dont know if this is true. i was told to just put the stock uppers back on and get adjustables. hopefully this is not necessary! i will loosen the control arms and then retighten them with the weight on the axles. i was told by UPR that these control arms where stock length too, but when compared the mounting holes where about 1/4" shorter than stock. also, is it normal on the uppers, after you attach the body side, to have to pull the arm about 1/2-3/4" just to get it over the bushings on the rearend? the uppers just seemed to have a lot of bind. i had to move the axle all over the place to get the bolt holes to line up on the rearend housing.
thanks again
 
V

v8only

Active Member
Jul 3, 2003
2,378
22
49
Apr 14, 2005
#7
  • Apr 14, 2005
  • #7
do what 89mustanggx suggested. Retorque the bolts in a simulated sitting position.
 
3

306lx

Member
Mar 31, 2005
44
0
6
bakersfield, ca
Apr 14, 2005
#8
  • Apr 14, 2005
  • #8
well i talked to maximum motorsports today and they said there is just too much pinion angle with the car being lowered and the new uppers being shorter. they also said it doesnt matter if the bolts where tightened with weight on the axle or not, which makes since because if it did matter, when you tightened the bolts with the axle at full droop then the rear of the car would be stuck in the air. they suggested just putting the stock uppers back on. so i think i will take them to work tomorrow and box them. they also said that the urethane bushing is too stiff and that ford designed it with a rubber bushing for a reason, so they sell bushings that are somewhere between rubber and urethane. so does anyone wanna buy some UPR upper control arms?
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Apr 14, 2005
#9
  • Apr 14, 2005
  • #9
I am not using these control arm, I have the old school Factory Five arms. I have had no problem with binding, even with the car being lowered. I do remember that the urethan bushing were supposed to be greased with chassis grease. Did you do this? It would help prevent binding, as well as those annoying squeaks.
 
3

306lx

Member
Mar 31, 2005
44
0
6
bakersfield, ca
Apr 14, 2005
#10
  • Apr 14, 2005
  • #10
yeah the arms came with grease from the factory. i believe the factory five arms are stock length and thats why they work. i tried everyone's suggestions and just test drove it. nothing changed. UPr told me to keep the bolts a little on the loose side, everyone else says to torque them to spec, well spec is 100 lb ft, from what i read? so i figured i tightened them by hand and surely that was no where near 100. i am still hung up on the fact that i had pull the rearend side of the upper mounts over about 3/4" just to get it on. thanks for all the advice!!
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Apr 14, 2005
#11
  • Apr 14, 2005
  • #11
So does upr intentionally make their product shorter than stock? If so, Why????
 

darthcual

Member
Mar 31, 2005
985
19
18
Arlington, TX
Apr 14, 2005
#12
  • Apr 14, 2005
  • #12
Hmm i think uprs are to tighten up handling? No? which means your launch will suffer. Maybe i'm wrong.
 

Blakthorn

Member
Jul 24, 2004
299
1
16
US
Apr 14, 2005
#13
  • Apr 14, 2005
  • #13
how about these for non-adjustables http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7967142987&category=33583

good/bad?
 

89MustangGX

I have nothing productive to add!
Jul 3, 2001
10,262
1
0
Mill Creek, WA
Apr 14, 2005
#14
  • Apr 14, 2005
  • #14
I suppose it's possible, but Maximum Motorsports doesn't reccommend anything other than stock control arms. Why not call UPR and see what they say?
 
3

306lx

Member
Mar 31, 2005
44
0
6
bakersfield, ca
Apr 15, 2005
#15
  • Apr 15, 2005
  • #15
of course i have already called UPR and asked their rep. his exact words were, we like to keep about a business cards width between the bolts and the flange, you just have them too tight. for some reason i dont thnk that is right. if you talk to 3 different people there you get 3 different answers. one guy told me no quad shocks, another told me their control arms where the exact lenght as stock, and the main guy this morning told me of course they are shorter to add pinion angle for launching, in the same sentence he told me lowering a car doesnt add any angle and that i should be fine, just take more pressure out of the tires and loosen the bolts. again, i dont think that is the answer. and like i said before, comparing stock vs UPR, UPR's uppers are about 1/4" shorter than stock and the fact that the stock uppers line right up with both mounting spots and UPR's i had to pry over the axle mounts. i am gonna check the pinion angle tomorrow and call them back and remind them that i asked them all these questions before i bought their product. i am sure it will all work out.
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Apr 15, 2005
#16
  • Apr 15, 2005
  • #16
306lx said:
i am sure it will all work out.
Click to expand...

Now that's a good joke!
I think the most likely answer is that upr got sloppy with their production tolerances and sold you a bad set. Take a measurement and see if it agrees with their production dwg.
 
3

306lx

Member
Mar 31, 2005
44
0
6
bakersfield, ca
Apr 15, 2005
#17
  • Apr 15, 2005
  • #17
i glad to see someone gets my sarcasm. anyway ill let you guys know how they do at the track tonight, if i dont get optimistic and put the stock uppers back on.
 
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