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Front end vibration at 65-70 MPH. Causes? by Dennis LaGrua
Started on: 06-25-2012 09:49 AM
Replies: 30 (5971 views)
Last post by: fierosound on 07-06-2013 11:03 AM
Dennis LaGrua
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06-25-2012 09:49 AM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post

My car has been experiencing a front end vibration when I reach 65-70 mph. Something is going on so I'll need to do the checks.
Here are the causes as I see them:
Out of balance tires- only a year old ,already balanced twice, still could be a balance problem. Need to check again
Tie rod , rod ends, and rack-- all changed last year.
Wheel Bearings - could be , but seem smooth on turning
Warped brake rotor- possible problem area. Calipers seem to work fine
Ball Joints- possible but they seem tight.

Everything is good until we reach 65 MPH so this would lead me to believe its the tires or a warped or even an out of balance rotor.
Anyone else experience this? Solutions? Opinions?

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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Gall757
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06-25-2012 10:07 AM Click Here to See the Profile for Gall757Click Here to Email Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post

2 more things to look for.

1. Bent wheel. hit anything lately?
2. Broken cord in the tires. Look for a distortion in the side wall.

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crashyoung
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06-25-2012 10:07 AM Click Here to See the Profile for crashyoungClick Here to Email crashyoungSend a Private Message to crashyoungEdit/Delete MessageReply w/QuoteDirect Link to This Post

Does it seem to come and go? I had a tire store employee think it was funny to throw some shop rags and other crap in my tires.
Needless to say, I do not use their chain (Discount tire) any more! I have had better luck with the name brand stores for good quality tires.

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Dennis LaGrua
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06-25-2012 12:07 PM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post

First analysis in the shop this morning indicates a very slight amount of movement when you grab the tire by both ends and push/pull.Suspect excessive clearance in the outer or inner tie rod but waiting for my helper to arrive so I can get under there with the stethoscope and find the noise. Tires and wheels appear to be OK.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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Bloozberry
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06-25-2012 12:15 PM Click Here to See the Profile for BloozberrySend a Private Message to BloozberryEdit/Delete MessageReply w/QuoteDirect Link to This Post

Another possible source is if you're using aftermarket wheels that are lug centric rather than hub centric. It can be tough to get lug centric wheels perfectly centered.

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06-25-2012 01:16 PM Click Here to See the Profile for AquaHuskyClick Here to Email AquaHuskySend a Private Message to AquaHuskyEdit/Delete MessageReply w/QuoteDirect Link to This Post

Another cause could be the car is scared to go that fast?

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Dennis LaGrua
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06-25-2012 02:34 PM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by Bloozberry:

Another possible source is if you're using aftermarket wheels that are lug centric rather than hub centric. It can be tough to get lug centric wheels perfectly centered.


Checking this out as well as the wheels do not appear to be hub centric. I will do a rotational test and measure if the tires are running true. However the rack (replaced last year) appears to have some side play on the passenger side. It looks like a poor rebuild job (Cardone brand) as you can move the shaft side to side a small amount and you can hear a knock. Replacing it with a rack that I personally rebuilt using Rodneys high quality rack bushing, Moog tie rods and rod ends. Everything else appears to be tight but the ball joints are under stress and difficult to test without compressing the springs.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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Pyrthian
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06-25-2012 03:37 PM Click Here to See the Profile for PyrthianClick Here to Email PyrthianSend a Private Message to PyrthianEdit/Delete MessageReply w/QuoteDirect Link to This Post

there is also shocks. a bad shock or loose shock mount will make a shaky wheel, especially at freeway speeds.

does it shake the steering wheel or the whole car?

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06-27-2012 04:54 PM Click Here to See the Profile for Trust oneClick Here to Email Trust oneSend a Private Message to Trust oneEdit/Delete MessageReply w/QuoteDirect Link to This Post


did you solve your front end vibration problem ?

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06-27-2012 05:16 PM Click Here to See the Profile for PhirewireClick Here to Email PhirewireSend a Private Message to PhirewireEdit/Delete MessageReply w/QuoteDirect Link to This Post

balancing and weight normal causes bouncing. Could it be an alignment issue?

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Dennis LaGrua
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06-27-2012 05:20 PM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by Trust one:


did you solve your front end vibration problem ?


Addressing the rack. Seemed a bit loose. Trying to rebuild but hit a snag.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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hercimer01
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06-27-2012 07:33 PM Click Here to See the Profile for hercimer01Send a Private Message to hercimer01Edit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by Dennis LaGrua:


Checking this out as well as the wheels do not appear to be hub centric. I will do a rotational test and measure if the tires are running true. However the rack (replaced last year) appears to have some side play on the passenger side. It looks like a poor rebuild job (Cardone brand) as you can move the shaft side to side a small amount and you can hear a knock. Replacing it with a rack that I personally rebuilt using Rodneys high quality rack bushing, Moog tie rods and rod ends. Everything else appears to be tight but the ball joints are under stress and difficult to test without compressing the springs.




I had a vibration and the tires were out of round due to age and storage.
When I put them on the back with it jacked up I could actually see them wobble a bit with the car idling in drive.
New tires solved my problem.

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jetsnvettes2000
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06-27-2012 08:16 PM Click Here to See the Profile for jetsnvettes2000Send a Private Message to jetsnvettes2000Edit/Delete MessageReply w/QuoteDirect Link to This Post

I just had same exact symptoms as you, as it turns out it was pretty bad I even drove 200+ miles to the dells and back with the rack like this:


Look at your rack under the mounts it was the cause of my shake at 70mph the rack case was cracked in half!!

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Dennis LaGrua
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06-28-2012 10:48 AM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by jetsnvettes2000:

I just had same exact symptoms as you, as it turns out it was pretty bad I even drove 200+ miles to the dells and back with the rack like this:


Look at your rack under the mounts it was the cause of my shake at 70mph the rack case was cracked in half!!


It looks as though the man upstairs was looking out for you. My rack had a slight amount of play in it but nothing major. Now if I can only find a way to align it and get it back together it might solve the problem.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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katore8105
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06-28-2012 01:35 PM Click Here to See the Profile for katore8105Click Here to visit katore8105's HomePageSend a Private Message to katore8105Edit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by jetsnvettes2000:

I just had same exact symptoms as you, as it turns out it was pretty bad I even drove 200+ miles to the dells and back with the rack like this:


Look at your rack under the mounts it was the cause of my shake at 70mph the rack case was cracked in half!!


My rack broke in this exact same place a couple of months ago when driving back to Syracuse from the "Support the Troops" show in Harrisburg. I also drove it for another 100+ miles just fine. Steering completly locked up on me on a mountain pass. I turned the wheel so hard, "POP" goes the steering rack.

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06-29-2012 08:39 PM Click Here to See the Profile for TimpilotClick Here to visit Timpilot's HomePageClick Here to Email TimpilotSend a Private Message to TimpilotEdit/Delete MessageReply w/QuoteDirect Link to This Post

My '88 Formula did the same thing - vibration at 65 to 70. My car has just under 60,000 miles. I changed inner and outer tie rod ends, steering rack bushing (replaced with Rodney's bronze bushing), and lower ball joints. Still had the vibration after each of those component changes. Then I changed the upper control arm (UCA) bushings and the vibration is gone.

If the UCA bushings haven't been changed, and even if they LOOK OK, they are probably cracked/mushy. Not real difficult to change if you rent a control arm bushing tool kit from Auto Zone. But you definitely have to go straight to an alignment shop afterward.

[This message has been edited by Timpilot (edited 06-29-2012).]

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Dennis LaGrua
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06-29-2012 09:19 PM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post

Rack is now rebuilt and in. Not sure id this will do it. If not I will disassemble the control arms and check the bushings.
UPDATE: Vibration better but not solved. Upper control arm bushings look to have stress cracks in them. On to removing the upper control arms for poly bushings. Don't look foward to pulling the ball joint but it needs to be done. Next weeks project is already spoken for. We have a set of poly bushings here but not sure if they will give a harsh ride or not. Anyone using front control arm bushings care to give an opinion on them? Already using them on the rear and notice a slightly harsher ride but to change the front?????
------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

[This message has been edited by Dennis LaGrua (edited 06-30-2012).]

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06-30-2012 03:21 PM Click Here to See the Profile for katore8105Click Here to visit katore8105's HomePageSend a Private Message to katore8105Edit/Delete MessageReply w/QuoteDirect Link to This Post

Yes, it will ride more rough. In my opinion however, The difference in handling is well worth the cost of feeling the road more. I would say the roughness is a 3 out of 10 increase but the handling is a 6 or 7 out of 10 increase.

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Dennis LaGrua
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06-30-2012 03:56 PM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by katore8105:

Yes, it will ride more rough. In my opinion however, The difference in handling is well worth the cost of feeling the road more. I would say the roughness is a 3 out of 10 increase but the handling is a 6 or 7 out of 10 increase.


It sounds as though the benefits of poly control arm bushings on the front outweigh the loss of some ride smoothness but a fair comparison may be new rubber vs new poly rather than old worn rubber bushings vs. new poly. Since we already have a set of Prothane bushings here so its on to to job number 1001 to get these bushings in. After owning several street/drag cars, I have come to accept better handling in lieu of a soft mushy ride.

Does anyone know if Autozone loans out a ball joint separator that can be used on a Fiero?. The one that we have here will not fit. In the worst case I guess that we can make one up but I'd rather spend time working on Fieros than building tools.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

[This message has been edited by Dennis LaGrua (edited 06-30-2012).]

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06-30-2012 06:30 PM Click Here to See the Profile for TimpilotClick Here to visit Timpilot's HomePageClick Here to Email TimpilotSend a Private Message to TimpilotEdit/Delete MessageReply w/QuoteDirect Link to This Post

Yes, Autozone has balljoint removal tool. I recently used their puller-type tool on my upper and lower balljoints and it worked great. This weekend, I just popped the uppers out with a prybar. Maybe it was easier because they'd been out within the past month or so.

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Dennis LaGrua
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06-30-2012 06:36 PM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by Timpilot:

Yes, Autozone has balljoint removal tool. I recently used their puller-type tool on my upper and lower balljoints and it worked great. This weekend, I just popped the uppers out with a prybar. Maybe it was easier because they'd been out within the past month or so.


Anyway you look at it replacing the front control arm bushings is a PITA job and one that requires extreme care. If that spring lets loose it can do some serious damage. I don't recommend this job for the novice.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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06-30-2012 07:17 PM Click Here to See the Profile for TimpilotClick Here to visit Timpilot's HomePageClick Here to Email TimpilotSend a Private Message to TimpilotEdit/Delete MessageReply w/QuoteDirect Link to This Post

The upper control arm is easy. I just did my second one yesterday. Less than two hours total to replace both bushings. I DID have to get creative in driving/pressing the old bushings out and the new ones in. The AutoZone control arm bushing tool kit worked PRETTY well. I used the AutoZone tool to start the bushings out, then finished by prying them out with a pickle fork tool. Driving a new bushing in can bend the second flange if you don't support it. If you do bend a flange, they are soft steel and easy to straighten. My flanges were straighter when I finished than when I started. It was very helpful to insert a hose clamp between the flanges to support them during removal and installation. I should have taken photos but it was 110-degrees and I wanted to get done.

BTW, I jacked the car up from under the lower control arm and the spring was not involved at all in removing and replacing the upper control arm.

[This message has been edited by Timpilot (edited 06-30-2012).]

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07-01-2012 07:58 PM Click Here to See the Profile for katore8105Click Here to visit katore8105's HomePageSend a Private Message to katore8105Edit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by Dennis LaGrua:
a fair comparison may be new rubber vs new poly rather than old worn rubber bushings vs. new poly. Since we already have a set of P


I agree with that. Would be interesting to see a controlled comparison on the same vehicle. A bit too much work for me though!

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Dennis LaGrua
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07-10-2012 09:18 PM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by Timpilot:

The upper control arm is easy. I just did my second one yesterday. Less than two hours total to replace both bushings. I DID have to get creative in driving/pressing the old bushings out and the new ones in. The AutoZone control arm bushing tool kit worked PRETTY well. I used the AutoZone tool to start the bushings out, then finished by prying them out with a pickle fork tool. Driving a new bushing in can bend the second flange if you don't support it. If you do bend a flange, they are soft steel and easy to straighten. My flanges were straighter when I finished than when I started. It was very helpful to insert a hose clamp between the flanges to support them during removal and installation. I should have taken photos but it was 110-degrees and I wanted to get done.

BTW, I jacked the car up from under the lower control arm and the spring was not involved at all in removing and replacing the upper control arm.



Finished the upper control arm poly bushings replacement job today in about 3 hours. It is a pretty easy job. You lift the car up support the lower control arm, remove the shock, brake hose rivet/bracket, cotter pin and nut that holds the upper ball joint, then use the special ball joint separation tool as shown in the Fiero manual. Its a Kent Moore tool that I keep on hand. When the upper joint is separated it is a simple matter of taking off the long bolt that holds the upper control arm in place and remembering where the spacer washers are placed. I used poly so getting those bushings in was simple. Removing the old rubber bushings from the sleeves is a quick job. All you need is a propane torch. Use it to heat the inner metal sleeve to red hot, then push it out with a large screwdriver. Keep the heat on the remaining rubber and push it out with the screwdriver. if you do it right all of the rubber will come out in one piece. Next I use scotchbrite to smooth the inner sleeves, paint the control arms, then grease the poly bushings in and out then push the greased sleeves in place. Putting them back takes about 20 minutes. Torque control arm bolt ( with the spacer washers and end washers in place) to 55 ft lbs and reattach the ball joint tightening the nut to 35 ft lbs and putting in a new cotter pin. Then I regrease the ball joint and clean the brake rotor before putting the whelel on. Now to test to see if that was the source of the vibration problem.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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Dennis LaGrua
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10-15-2012 12:44 PM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post

After rebuilding the rack, replacing the upper control arm bushings, upper ball joints, rechecking and replaced/ rebalanced the tires. Brakes are relatively new. Wheels now use hubcentric rings and appear to spin true. KYB shocks are not that old like 300 miles. After all that the vibration is still there. You can feel it in the steering wheel. The only thing that we haven't replaced is the lower ball joint and control arm bushings but everything seems tight. . The 65-70 mph vibration is still there and driving me nuts.
I am beginning to believe that the rotors themselves may be out of balance or I might just remove the lower control arm and check everything out.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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Duck Hunter 117
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10-15-2012 01:36 PM Click Here to See the Profile for Duck Hunter 117Send a Private Message to Duck Hunter 117Edit/Delete MessageReply w/QuoteDirect Link to This Post

Have you checked the bearings yet? I had a RF bearing fail that would cause I vibration when turning right at high speeds. The wheel didn't have any wobble, bearing spun free, and no strange noises. However, when I pulled the bearing off I could spin the outer race with just my finger and really light pressure. Replaced the bearing and its been great since.

Can you swap the front and rear tires for a short test drive to eliminate that component?

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rourke_87_T-Top
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10-15-2012 03:20 PM Click Here to See the Profile for rourke_87_T-TopClick Here to Email rourke_87_T-TopSend a Private Message to rourke_87_T-TopEdit/Delete MessageReply w/QuoteDirect Link to This Post

What year is this car ? The reason I ask, on pre '88, the crossmember sleeve that the upper control arm goes through wears out, the bolt is harder steel and it eggs the very short and soft mild steel, inside the short length of tube, causing oscillation, if you remove the wheel, jack it with the suspension compressed, shake the rotor at 3 O'clock and 9 O'clock, watch closely the upper A arm bolt for movement, it will move a few degrees, if it is severely worn, you will see the A arm pitch fore and aft. Even with new bushings, ball joints etc. I've mentioned this a few times, poor design, long bolt in the very short sleeve, it needs bracing at the outer ends of the bolt . To limit deflection. The upper bolts will also be very polished from wearing out the sleeve.

[This message has been edited by rourke_87_T-Top (edited 10-15-2012).]

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Dennis LaGrua
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10-15-2012 06:04 PM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by rourke_87_T-Top:

What year is this car ? The reason I ask, on pre '88, the crossmember sleeve that the upper control arm goes through wears out, the bolt is harder steel and it eggs the very short and soft mild steel, inside the short length of tube, causing oscillation, if you remove the wheel, jack it with the suspension compressed, shake the rotor at 3 O'clock and 9 O'clock, watch closely the upper A arm bolt for movement, it will move a few degrees, if it is severely worn, you will see the A arm pitch fore and aft. Even with new bushings, ball joints etc. I've mentioned this a few times, poor design, long bolt in the very short sleeve, it needs bracing at the outer ends of the bolt . To limit deflection. The upper bolts will also be very polished from wearing out the sleeve.



We'll give it a look. The car only has 67K miles on it but anything is possible. .

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
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87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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rourke_87_T-Top
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From: Toronto Ontario Canada
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10-15-2012 06:50 PM Click Here to See the Profile for rourke_87_T-TopClick Here to Email rourke_87_T-TopSend a Private Message to rourke_87_T-TopEdit/Delete MessageReply w/QuoteDirect Link to This Post

...and when it starts to get very severe you will notice a clunk noise every time you hit the brakes at lower speeds. That is the upper arm, the long bolt to be more precise.

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Dennis LaGrua
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From: Hillsborough, NJ U.S.A.
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10-15-2012 10:03 PM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by rourke_87_T-Top:

...and when it starts to get very severe you will notice a clunk noise every time you hit the brakes at lower speeds. That is the upper arm, the long bolt to be more precise.


We'll check it out but need to first test run with the new tire balancing re-done today. Tire place said that they found about 1/2 oz error in the weights but thats not very much. If that fails then we will disassemble all the suspension parts and recheck everything. You say that its possible for the mounting holes where the control arm long bolt fits though the mounting bracket could be elongated so we will see.

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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fierosound
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From: Calgary, Canada
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07-06-2013 11:03 AM Click Here to See the Profile for fierosoundClick Here to visit fierosound's HomePageClick Here to Email fierosoundSend a Private Message to fierosoundEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by Dennis LaGrua:

I am beginning to believe that the rotors themselves may be out of balance or I might just remove the lower control arm and check everything out.



Have you found a place that does "on car balancing"?

Years ago I had a problem with a car and that was the only thing that solved it.

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