Pennock's Fiero Forum
  General Fiero Chat
  HELP! Handling suspension problem - car "wanders" at speed

Post New Topic  Post A Reply
Email This Page to Someone! | Printable Version


next newest topic | next oldest topic
HELP! Handling suspension problem - car "wanders" at speed by trivet
Started on: 06-13-2016 02:25 PM
Replies: 13 (387 views)
Last post by: KaijuSenso on 06-18-2016 08:53 PM
trivet
Member
Posts: 783
From: Bay City, MI
Registered: Apr 2012


Feedback score:    (7)
Leave feedback

Rate this member

Report this Post06-13-2016 02:25 PM Click Here to See the Profile for trivetSend a Private Message to trivetEdit/Delete MessageReply w/QuoteDirect Link to This Post
I need some help – I have had a suspension/handling problem for several months, and I can’t get it corrected.
Car drives fine around town, but at highway speeds (60 mph+) it is a fight to keep it in a straight line. It can be so bad it’s scary to drive.

I had a similar issue about 2 years ago, replaced a rear wheel bearing- was perfect again. This felt like the same thing. New wheel bearings (both rear) new rear inner and out tie rods – same time added new Eibach springs. Was as bad as before: un-drivable.

1987 GT – very good condition, rust free and solid frame, all stock with the following exceptions:
The car has all poly suspension – about 4 years old, less than 5000 miles on it since. She handled BEAUTIFULLY when I had that done.
17 inch wheels added the same time the poly was (215/45/17 tires)
Eibach springs
Alignment is good (done with wheel bearings and tie rods)

This car drove PERFECTLY for 2 years, until I had the issue with the wheel bearing – fixed that, good for 2 more years, then handling was lousy again. Replaced everything listed above. Still handles terribly..

I’m fortunate to have a good mechanic that knows the car – but he is stumped as well. This is the first time he hasn’t been able to fix any issue I’ve had.

Any help is appreciated!

------------------
Tim
'87 GT
Med Red Metallic
85K miles
Bay City, MI

IP: Logged
PFF
System Bot
tebailey
Member
Posts: 2622
From: Bay City MI
Registered: Jan 2013


Feedback score: N/A
Leave feedback

Rate this member

Report this Post06-13-2016 03:54 PM Click Here to See the Profile for tebaileySend a Private Message to tebaileyEdit/Delete MessageReply w/QuoteDirect Link to This Post
Did you check the alignment after you changed the spring? My 84 had the same handling problem above 45 until I check the rear and found the toe was WAY off. Got the rear adjusted out right and it made a world of difference.
IP: Logged
trivet
Member
Posts: 783
From: Bay City, MI
Registered: Apr 2012


Feedback score:    (7)
Leave feedback

Rate this member

Report this Post06-13-2016 04:01 PM Click Here to See the Profile for trivetSend a Private Message to trivetEdit/Delete MessageReply w/QuoteDirect Link to This Post
Yes - alignment was done after all other work was performed (wheel bearings, tie rods, and springs).
IP: Logged
cvxjet
Member
Posts: 3648
From: ca, usa
Registered: May 2010


Feedback score: (1)
Leave feedback

Rate this member

Report this Post06-13-2016 04:24 PM Click Here to See the Profile for cvxjetSend a Private Message to cvxjetEdit/Delete MessageReply w/QuoteDirect Link to This Post
I can only suggest one possibility; I had a problem with my 85- At freeway speeds, if you accel'd it would pull to one side...Then if you deccel'd it would pull the other way....It turned out to be a leaking strut- As I was inspecting the suspension, i noticed some fluid on the strut- it was relatively subtle.....Pulled the strut(Mark your alignment and get a spring compressor) and when I pushed it down, it would not come back up. The fluid pointed to a leak, but the real problem was that ALL the pressure was released.

Check your struts- It really felt like someone was turning the wheel- Spooky!
IP: Logged
Gall757
Member
Posts: 10938
From: Holland, MI
Registered: Jun 2010


Feedback score: N/A
Leave feedback





Total ratings: 90
Rate this member

Report this Post06-13-2016 05:58 PM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
How much do you trust your alignment guy? Improper toe on the rear will wander

or maybe something slipped...

[This message has been edited by Gall757 (edited 06-13-2016).]

IP: Logged
trivet
Member
Posts: 783
From: Bay City, MI
Registered: Apr 2012


Feedback score:    (7)
Leave feedback

Rate this member

Report this Post06-13-2016 06:59 PM Click Here to See the Profile for trivetSend a Private Message to trivetEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by cvxjet:

I can only suggest one possibility; I had a problem with my 85- At freeway speeds, if you accel'd it would pull to one side...Then if you deccel'd it would pull the other way....It turned out to be a leaking strut- As I was inspecting the suspension, i noticed some fluid on the strut- it was relatively subtle.....Pulled the strut(Mark your alignment and get a spring compressor) and when I pushed it down, it would not come back up. The fluid pointed to a leak, but the real problem was that ALL the pressure was released.

Check your struts- It really felt like someone was turning the wheel- Spooky!



Shocks and struts were done the same time as the poly- new Monroe Sensatrak. Only about 5000 miles on them.


 
quote
Originally posted by Gall757:

How much do you trust your alignment guy? Improper toe on the rear will wander

or maybe something slipped...




I trust him completely - not saying he couldn't have made a mistake, but he is one of the VERY few I will let touch my car. He know Fieros and has been able to solve any other mystery I've had with it.
IP: Logged
cvxjet
Member
Posts: 3648
From: ca, usa
Registered: May 2010


Feedback score: (1)
Leave feedback

Rate this member

Report this Post06-13-2016 08:10 PM Click Here to See the Profile for cvxjetSend a Private Message to cvxjetEdit/Delete MessageReply w/QuoteDirect Link to This Post
I want to add- I know for a fact that my strut/spindle bolts were properly torqued to 140 lbs- I hit a very bad hump in the middle of a turn...almost lost it- got it under control and drove it home...A few days later I happened to notice that one rear wheel was at an odd angle- Those bolts had slipped.....Something to check......Enough force cam make even a properly torqued bolt slip....
IP: Logged
IanT720
Member
Posts: 1703
From: Whitmore Lake, MI
Registered: Sep 2010


Feedback score:    (9)
Leave feedback

Rate this member

Report this Post06-14-2016 09:20 AM Click Here to See the Profile for IanT720Send a Private Message to IanT720Edit/Delete MessageReply w/QuoteDirect Link to This Post
Low tire pressure, bad rear toe angle... For me my front wheel bearings were toasted! I knew I had some play in the front end but it wasn't terrible. One day I jacked up the car and grabbed the wheels... Both had 2-3" on play!!! Just on a Fiero with the weight in the back it wasn't that noticeable. It was much better after that.
IP: Logged
2.5
Member
Posts: 43224
From: Southern MN
Registered: May 2007


Feedback score: (1)
Leave feedback





Total ratings: 184
Rate this member

Report this Post06-14-2016 10:04 AM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
Some other possibilities to check are cradle or trans/engine mount bolts loose.
IP: Logged
Supracoupe
Member
Posts: 111
From: Ralston, OK, USA
Registered: Dec 2015


Feedback score:    (7)
Leave feedback

Rate this member

Report this Post06-14-2016 11:10 PM Click Here to See the Profile for SupracoupeSend a Private Message to SupracoupeEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by 2.5:

Some other possibilities to check are cradle or trans/engine mount bolts loose.


+1 on that and +1 on finding a good shop. . My problem was similar. New Eibach prings, Koni struts, new wheels and tires, new front and rear sway bars, and it was all over the road. Replaced the front tie rods and steering rack (rack had slop). Would get it checked out and aligned and the 1st two shops said every thing looked good. They would align it and it would last less than a day. I finally took it to a highly recommended independent shop and they found a loose cradle bolt and a bad lower ball joint on the same side. Almost 1/2 in of slack in the ball joint. Not sure how the other shops missed it. Turned out the cradle bolt would not stay torqued. Appears to have been stretched at some point in the past. The car was all over the road, and almost unsafe aver 65 miles per hour, requiring you FULL attention. I replaced the ball joint (both bottom rears actually) and installed a new cradle bolt with lock tight. Realigned and tracks straight and true now and any speed. Drove me nuts for about a month.
IP: Logged
Kevin87FieroGT
Member
Posts: 1202
From: Michigan
Registered: Nov 2010


Feedback score: (2)
Leave feedback

Rate this member

Report this Post06-15-2016 08:31 AM Click Here to See the Profile for Kevin87FieroGTSend a Private Message to Kevin87FieroGTEdit/Delete MessageReply w/QuoteDirect Link to This Post
It may be as simple as adjusting the steering pinion lash on your rack. Loosen the lock nut and adjust the inner nut by only 1/16th of a turn at a time, till the steering feels good. Mark the inner nut and lock nut before you start the process to index your adjustments. Clockwise tighter, counter clockwise looser. Makes a huge difference. Over time the nylon lash adjustment pad that runs against the rack wears slightly causing looseness at highway speeds. Considering all your other suspension parts are tight (ball joints, tie rod ends, control arm bushings, etc.) and tires good and inflated properly, this should fix it.

Beyond this, you could have a bad universal on the steering column shaft, located on the shaft just above the connection to the rack.

[This message has been edited by Kevin87FieroGT (edited 06-15-2016).]

IP: Logged
PFF
System Bot
trivet
Member
Posts: 783
From: Bay City, MI
Registered: Apr 2012


Feedback score:    (7)
Leave feedback

Rate this member

Report this Post06-15-2016 09:11 AM Click Here to See the Profile for trivetSend a Private Message to trivetEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Supracoupe:


+1 on that and +1 on finding a good shop. . My problem was similar. New Eibach prings, Koni struts, new wheels and tires, new front and rear sway bars, and it was all over the road. Replaced the front tie rods and steering rack (rack had slop). Would get it checked out and aligned and the 1st two shops said every thing looked good. They would align it and it would last less than a day. I finally took it to a highly recommended independent shop and they found a loose cradle bolt and a bad lower ball joint on the same side. Almost 1/2 in of slack in the ball joint. Not sure how the other shops missed it. Turned out the cradle bolt would not stay torqued. Appears to have been stretched at some point in the past. The car was all over the road, and almost unsafe aver 65 miles per hour, requiring you FULL attention. I replaced the ball joint (both bottom rears actually) and installed a new cradle bolt with lock tight. Realigned and tracks straight and true now and any speed. Drove me nuts for about a month.


That sounds VERY much like what I'm experiencing. I haven't had time to do much with it this week, but hopefully this weekend will allow me some time to look into this. It feels like the rear end is "loose" at highway speeds......this will be the next thing I check.

[This message has been edited by trivet (edited 06-15-2016).]

IP: Logged
Kitskaboodle
Member
Posts: 2988
From: San Jose, Ca.
Registered: Nov 2004


Feedback score:    (8)
Leave feedback

Rate this member

Report this Post06-18-2016 08:33 PM Click Here to See the Profile for KitskaboodleSend a Private Message to KitskaboodleEdit/Delete MessageReply w/QuoteDirect Link to This Post
Rear tie rods tight?
Front wheel bearings tight?
Rear tire condition?
If you have replacement ball joints, they might have loose nuts since you put them on.(3 per ball joint) My rear ones were dangerously loose despite putting them on with split washers. Most aftermarket ones are bolt & nut variety and can come loose. And I bought good ones too. (Rodney's) This is what made my 85 GT handle very bad in the rear. Almost had to change my underwear...
Kit
IP: Logged
KaijuSenso
Member
Posts: 911
From: Westland, MI
Registered: Jan 2007


Feedback score: (1)
Leave feedback

Rate this member

Report this Post06-18-2016 08:53 PM Click Here to See the Profile for KaijuSensoSend a Private Message to KaijuSensoEdit/Delete MessageReply w/QuoteDirect Link to This Post
I had a similar issue on my 86GT, turned out to be the large bolts that mounted the rear strut to the knuckle were loose. When the rear is in the air, you can notice the clunk by doing the 12 and 6 o'clock wiggle on the wheel. Took it to get aligned, told the guys what was loose so they could tighten it and realign (I didn't have nearly that large of a size socket/wrench) turns out they were telling me nothing was loose and I had to fight with them to align the darn thing right.

Anyway point being check the rear strut to knuckle bolts for being loose with no weight on the tire.
IP: Logged

next newest topic | next oldest topic

All times are ET (US)

Post New Topic  Post A Reply
Hop to:

Contact Us | Back To Main Page

Advertizing on PFF | Fiero Parts Vendors
PFF Merchandise | Fiero Gallery | Ogre's Cave
Real-Time Chat | Fiero Related Auctions on eBay



Copyright (c) 1999, C. Pennock