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Steering wobble at 60

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I get a light wobble/shutter at 60, sometimes it is there sometimes not, and what seems to really bring it on is a hard acceleration which I can then feel it around 40, but again it is a light wobble/shutter. I originally thought it could be the wheels needing balancing but I just rotated the tires and still have the same issue, unless all 4 need to be balanced again. Anyone have ideas on what could be causing this?
 
F.D. Sako said:
I guess first thing you could visually check is front bushings and tie-rods. Worst possible case, it could be bad steering rack?

I'll have to check that the next time I am under the car.
 
JScheier said:
When did the issue start? Have you done any modifications? Hit any potholes or curbs? Front bushings all OEM?
Everything bushing wise is OEM, though I do have Koni struts and GC CC plates. Honestly I think it started maybe a month or two ago, my memory is all whacked (genetic, not drug related, not entirely). I haven't hit any curbs or potholes recently either.
 

JScheier

Too Hot for the Boss!
If it's all OEM, I'd start with checking the suspension components for play / tightness:

* Make sure the struts are both securely connected
* Check tie-rod ends / ball joints
* Check for play in the front wheel bearings

It's pretty unlikely that all four wheels would be out of balance, so your rotation of the wheels should have resolved the problem if it was a wheel balance issue.

There have been reported issues with the EPAS (electronic steering) on earlier mustangs, but I've only seen / heard of it on GTs, not on the Boss 302s. You can google Mustang Steering Nibble or Mustang EPAS Problems and read about it.
 

302 Hi Pro

Boss 302 - Racing Legend to Modern Muscle Car
2,009
441
Southeast
Hi Brandon302:

Where and how do you feel this wobble and/or shutter? Steering wheel? Drivers seat? Any noise associated with the wobble? Let us know.

Inspection of components is a good place to start, but let us know where you feel this wobble.
Thanks,
Dave
 
302 Hi Pro said:
Hi Brandon302:

Where and how do you feel this wobble and/or shutter? Steering wheel? Drivers seat? Any noise associated with the wobble? Let us know.

Inspection of components is a good place to start, but let us know where you feel this wobble.
Thanks,
Dave

I can see the steering wheel shutter but the car tracks completely straight, though I can't entirely feel it unless I go to switch lanes and then I feel it for a short second and then it is gone. I can also feel something at my feet by the peddles but I will have to check and see if they seem to happen at the same time or if that is unrelated.
 

302 Hi Pro

Boss 302 - Racing Legend to Modern Muscle Car
2,009
441
Southeast
Brandon302 said:
I can see the steering wheel shutter but the car tracks completely straight, though I can't entirely feel it unless I go to switch lanes and then I feel it for a short second and then it is gone. I can also feel something at my feet by the peddles but I will have to check and see if they seem to happen at the same time or if that is unrelated.

Interesting that it only happens during a lane change and I'm guessing it's at 45 - 65 mph. Rules out wheel/tire balance issues in my mind.

Are the Koni sports, plates fairly new? As in this began after the install? If so, you should also check top strut mounting bolts again for torque. Then continue to check the steering and front suspension systems as mentioned by members above. Start with the simple things first, including tire pressure.

Good luck and keep us posted with your findings.

Dave
Hi Pro
 
302 Hi Pro said:
Interesting that it only happens during a lane change and I'm guessing it's at 45 - 65 mph. Rules out wheel/tire balance issues in my mind.

Are the Koni sports, plates fairly new? As in this began after the install? If so, you should also check top strut mounting bolts again for torque. Then continue to check the steering and front suspension systems as mentioned by members above. Start with the simple things first, including tire pressure.

Good luck and keep us posted with your findings.

Dave
Hi Pro

So I did drive the car today and it is noticeable both visually and tacitly and really only when going straight. I am wondering if it isn't something with the EPAS. The Koni's have been on for about 9 months and the issue just started about a month ago.
 
173
38
Wheel balance is the most likely cause.
It is always the first place to start when you feel the wheel shimmy.
A dial indicator on the outside of the rim will tell you if the wheel is running true or not.
I've been fighting this on my Boss since I changed to the GT500 six piston setup.
It started as soon as I installed the brake kit.I rebalanced the tires a few times and no help.
Got the dial indicator out and found the RF rim had .0055" of runout.
Removed tire/rim,refastened the rotor, set torque to 100 lb/ft and dialed the outer edge face of the rotor hub.
I found .0015" runout there.Removed rotor and dialed outer hub face,it was perfect.
Took a long fine file and lightly dressed the outside of the rotor hub face and the problem solved was solved.
That was the first incorrectly machined rotor I ever saw and I've installed thousands.
Thanks, Guy
 

302 Hi Pro

Boss 302 - Racing Legend to Modern Muscle Car
2,009
441
Southeast
Brandon302 said:
So I did drive the car today and it is noticeable both visually and tacitly and really only when going straight. I am wondering if it isn't something with the EPAS. The Koni's have been on for about 9 months and the issue just started about a month ago.

So if the wobble shimmy is happening to you while going straight, and not just on lane changes that varies the front suspension load, I too would start with wheels and tires. Wished we had an internet test drive button to click on! LoL.

Good advice from gww52, I would start there.

Dave
 
gww52 said:
Wheel balance is the most likely cause.
It is always the first place to start when you feel the wheel shimmy.
A dial indicator on the outside of the rim will tell you if the wheel is running true or not.
I've been fighting this on my Boss since I changed to the GT500 six piston setup.
It started as soon as I installed the brake kit.I rebalanced the tires a few times and no help.
Got the dial indicator out and found the RF rim had .0055" of runout.
Removed tire/rim,refastened the rotor, set torque to 100 lb/ft and dialed the outer edge face of the rotor hub.
I found .0015" runout there.Removed rotor and dialed outer hub face,it was perfect.
Took a long fine file and lightly dressed the outside of the rotor hub face and the problem solved was solved.
That was the first incorrectly machined rotor I ever saw and I've installed thousands.
Thanks, Guy

What do you mean a dial indicator?
 

steveespo

Lord knows I'm a Voodoo Child
Moderator
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Cookeville TN
gww52 said:
Wheel balance is the most likely cause.
It is always the first place to start when you feel the wheel shimmy.
A dial indicator on the outside of the rim will tell you if the wheel is running true or not.
I've been fighting this on my Boss since I changed to the GT500 six piston setup.
It started as soon as I installed the brake kit.I rebalanced the tires a few times and no help.
Got the dial indicator out and found the RF rim had .0055" of runout.
Removed tire/rim,refastened the rotor, set torque to 100 lb/ft and dialed the outer edge face of the rotor hub.
I found .0015" runout there.Removed rotor and dialed outer hub face,it was perfect.
Took a long fine file and lightly dressed the outside of the rotor hub face and the problem solved was solved.
That was the first incorrectly machined rotor I ever saw and I've installed thousands.

Guy is correct, also junk on the hub, rotor or wheel mounting surface can cause vibrations. If you have changed or rotated wheels check those mounting surfaces closely.
Steve
Thanks, Guy
 
If it could be something on the mounting surface I wonder if the clip that hols the rotor on could be causing this.
 

302 Hi Pro

Boss 302 - Racing Legend to Modern Muscle Car
2,009
441
Southeast
Brandon302 said:
If it could be something on the mounting surface I wonder if the clip that hols the rotor on could be causing this.

Brandon302:

Yes, it very well maybe the Rotor circle clips used by Ford during the assembly process of our cars. The OEM and other wheels offered by FRPP have allowances for these clips drilled out on the inner mounting surface of the wheel.

Many aftermarket wheels do not have provisions for the clips and if mounted with the clips in place, the wheel will not seat properly when mounted.

Not sure if you have begun to inspect anything yet, but the best advice from members here that I have seen is to "Start with the easy things first" You should have your wheel balance checked by a shop. I have my wheels and tires balanced on a Road Force, (some call this Load Force), balance machine that does an excellent job.

Keep us posted as to what you have checked so far.
Thanks,
Dave
 
302 Hi Pro said:
Brandon302:

Yes, it very well maybe the Rotor circle clips used by Ford during the assembly process of our cars. The OEM and other wheels offered by FRPP have allowances for these clips drilled out on the inner mounting surface of the wheel.

Many aftermarket wheels do not have provisions for the clips and if mounted with the clips in place, the wheel will not seat properly when mounted.

Not sure if you have begun to inspect anything yet, but the best advice from members here that I have seen is to "Start with the easy things first" You should have your wheel balance checked by a shop. I have my wheels and tires balanced on a Road Force, (some call this Load Force), balance machine that does an excellent job.

Keep us posted as to what you have checked so far.
Thanks,
Dave

I think I will be starting with a balance as that would be cheaper than the rest of the fixes, I haven't had time to do this recently but will hopefully get around to it soon.
 

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