I think I found the front end highway wander issue with my 88GT, help! (Page 1/3)
phils88GT SEP 15, 09:55 PM
So this evening I decided to pull off the front wheels and have a look at my front suspension on my 88 GT. The problem I was having was mostly when hitting dips or long bumps at highway speeds, the front end would unevenly bounce and kind of wander. IT was violent, but if you are not prepared, it can be kind of unnerving.

What I had already done was replace the upper and lower ball joints, front outer tie rods and new front and rear KYB shocks. I did NOT replace any of the front bushings in the control arms, as they seemed ok, but I could be wrong.

Anyway, I had the car aligned and it aligned ok. She doesn't pull at all at any time. All of the tires are new stock 15" size tires as well. There is no vibration, no slack in the steering and other than that, is a pretty good ride for a car that is almost 35 years old.

Back to my discovery this evening. I did do a check on both sides for play in the wheels. On the passenger side, when grabbing the wheel at 12 and 6, you could rock the wheel about 1.5mm in and out. at 3 and 9, there was no movement. I looked at the suspension when rocking the tire on the vertical 12 and 6, and everything was stationary except for the rotor, which I can only assume that it means the wheel bearing needs to be replaced. I have searched high and low, and found the Rodney Dickman is pretty much the only person carrying these. Does it sound like the bearing is the problem? Are the RD hubs pretty good? Plug and play?

One other thing I noticed that on the driver side, with both wheels off and suspension unloaded, the location of the upper sway bar nut was not in the same location. I should have gotten some pics, but I was in a hurry. But, if you are standing and looking down at the the upper control arm on the passenger side, you can see the nut at the top of the end link sticking just outside of the upper control arm. When I went to the driver side, that same nut on the end of the end link is tucked under the upper control arm. The long bolt and sleeve on both sides is straight, but, on the driver side, where the sway bar exits the bushing and does a hard turn and runs down the frame, it looks different than the passenger side. I need to get pictures, but it doesn't look right. I should note also that when I did the LCA ball joints on the driver side, the actual shaft on that lower front ball joint was bent! Yep, bent slightly, but bent to the point where you could easily see the damage. Some idiot has aligned the car with this problem! So, it stands to reason, in my head, that whatever happened could have cause the damage to the front sway bar as well? What kind of symptoms would you have with the vertical play on the passenger side and the possible bent sway bar?

Thanks everyone!
Patrick SEP 15, 10:07 PM

quote
Originally posted by phils88GT:

On the passenger side, when grabbing the wheel at 12 and 6, you could rock the wheel about 1.5mm in and out. at 3 and 9, there was no movement. I looked at the suspension when rocking the tire on the vertical 12 and 6, and everything was stationary except for the rotor, which I can only assume that it means the wheel bearing needs to be replaced.



I'm definitely no expert on this, but I'd suspect with worn wheel bearings that the wheel would rock if there was play no matter where the wheel was gripped. I know you said you replaced them, but I'd suspect worn/loose ball joints.


quote
Originally posted by phils88GT:

One other thing I noticed that on the driver side, with both wheels off and suspension unloaded, the location of the upper sway bar nut was not in the same location. But, if you are standing and looking down at the the upper control arm on the passenger side, you can see the nut at the top of the end link sticking just outside of the upper control arm. When I went to the driver side, that same nut on the end of the end link is tucked under the upper control arm. The long bolt and sleeve on both sides is straight, but, on the driver side, where the sway bar exits the bushing and does a hard turn and runs down the frame, it looks different than the passenger side. I need to get pictures, but it doesn't look right. I should note also that when I did the LCA ball joints on the driver side, the actual shaft on that lower front ball joint was bent! Yep, bent slightly, but bent to the point where you could easily see the damage. Some idiot has aligned the car with this problem! So, it stands to reason, in my head, that whatever happened could have cause the damage to the front sway bar as well? What kind of symptoms would you have with the vertical play on the passenger side and the possible bent sway bar?

I should have gotten some pics, but I was in a hurry.



It would have taken you less time to take and upload a couple of photos than to type that all out... and we'd know what the heck you were talking about!

[This message has been edited by Patrick (edited 09-15-2024).]

sleek fiero SEP 15, 10:33 PM
If the front ball joint shaft was bent I would suspect the control arm itself would be damaged and or the spindle. I would do some serious disassembly and inspection to find out the total amount of damage. Your life could depend on it. sleek
Dennis LaGrua SEP 16, 06:07 AM
You have described what is commonly known as a "bump steer" problem. There could be many causes including worn bushings but when the problem surfaced on my GT it was just an out of alignment issue.

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cartercarbaficionado SEP 16, 06:35 AM

quote
Originally posted by Dennis LaGrua:

You have described what is commonly known as a "bump steer" problem. There could be many causes including worn bushings but when the problem surfaced on my GT it was just an out of alignment issue.



see the important thing is that it's an 88.
the 88 suspension specifically has twice the bumpsteer than the earlier models due to the elimination of the steering damper and the changes in geometry also do not help at all.
the solution to the bump steer issue is to align the car differently and be very very conscious about what is and is not happening. my formula has huge bump steer issues and fishtailing at high speeds due to the front suspension behaving the same way when loaded and unloaded rapidly.
I recommend he checks his shock absorbers and he should absolutely replace his sway bar bushings and wheel bearings and do the bushings if he has not already. every 88 needs these checked
Yellow-88 SEP 18, 11:25 AM

quote
Originally posted by cartercarbaficionado:

see the important thing is that it's an 88.
the 88 suspension specifically has twice the bumpsteer than the earlier models due to the elimination of the steering damper and the changes in geometry also do not help at all.



This is completely incorrect. The 88 chassis is well designed and far superior than the early cars.

The issues described here are typical of worn or damaged front end components.
Yellow-88 SEP 18, 11:37 AM

quote
Originally posted by phils88GT:

Anyway, I had the car aligned and it aligned ok. She doesn't pull at all at any time. All of the tires are new stock 15" size tires as well. There is no vibration, no slack in the steering and other than that, is a pretty good ride for a car that is almost 35 years old.




So is everything OK now? Or are there still issues. It's hard to tell from your post.
Was the alignment done without checking for worn or damaged parts?
phils88GT SEP 18, 06:58 PM

quote
Originally posted by Yellow-88:


So is everything OK now? Or are there still issues. It's hard to tell from your post.
Was the alignment done without checking for worn or damaged parts?



Sorry I have not posted back yet. By the time I get home at night, it is usually too late to do anything because it is getting dark sooner.

So here are a couple of pics from side to side.

Tried to get the angle right….
phils88GT SEP 18, 07:02 PM

quote
Originally posted by phils88GT:


Sorry I have not posted back yet. By the time I get home at night, it is usually too late to do anything because it is getting dark sooner.

So here are a couple of pics from side to side.
The front suspension is totally unloaded.
Tried to get the angle right….
fieroguru SEP 18, 08:02 PM
The sway bar brackets have some slop in the positioning.
The front crossmember is only pinned on one side, so the other side can be forward or back from there.
The Upper A-arm also has a lot of movement with the slotted upper a-arm holes.

Before getting too concerned with the position of the end links. Check the caster setting from side to side and check the wheel base from side to side. If either of those is different, it could easily explain the sway bar end link issue.

Also with 88s, never forget the long bolt in the rear suspension lateral links. It is often loose and will cause the car to dart all over the place.