Rear suspension squeak

Hurricane cobra

Registered User
I have a Shelby cobra replica with Thunderbird/Mark VIII knuckles on the rear as part of my IRS. I've started developing a squeak in the rear suspension and I suspect the bushings on the UCAs and maybe the bushings on the knuckle as well. It's relatively easy to remove and grease the bushings on the UCA, but as I've learned from this forum, it's no easy task to remove and replace the knuckle bushings.
My question to your T'bird experts is how likely do you think the squeak is from the knuckle bushings?
Attached is a picture of my IRS setup.
Thanks for your help
Matt
 

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I don't know about your squeak BUT THAT IS A SWEET SET UP!!!

I bet he doesn't get wheel hop with the UCA being a A-Arm!

We need to get that set up to work on a stock body!

Where is the spring mounted too? Coilover?

MANY MORE PICS WOULD BE GREAT!!


By the way... WELCOME to the site!
 
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Thanks for the compliment!
Here's a build picture that shows the rear end set up installed.
I'm running coilovers on QA-1 shocks
No, I don't get any wheel hop, buy with 560 ft. lbs of torque in a 2700 lb car, I do get alot of wheel spin, but only in the first 4 gears:p
Matt
 

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Knuckle bushing should not squeak. The lower bushings are pressed into the knuckle and clamped with the bolts meaning that they do not rotate but instead the only motion as the suspension articulates is in the deflection of the rubber. If they are squeaking that indicates that they may be torn internally and need replacing. It is important when tightening these lower bolts that you have the arm in it's normal loaded position so that under normal driving circumstances the bushings are not loaded.

The top bushing has a nylon insert with lubrication that allows free rotation of the upper arm mounting point. If the stock unequal length control arm setup (shorter upper arm) has been retained, this means that the upper arm travels through more of an arc as the suspension travels, hence why it has a free rotating bushing in it as opposed to the solid style lower bushings.

Now looking at your setup, it appears that you have replaced the upper bushing with a poly bushing, at least it does not appear to be stock. If this is the case, then I suspect this may be the source of your squeak. Aftermarket poly bushings may not rotate properly compared to the original design. If it is aftermarket poly, you can probably remove the inner sleeve and lubricate it. You could also drill and tap the knuckle for installing a grease fitting.
 
Poly tends to squeek if its cold out? Is it cold where your at? SOme silicone will help for awhile if thats the case
 
just noticed the rotors... Drilled for the 4.5" bolt pattern.

probably other stuff I mised too but either way...
THAT IS A COOL SET UP!!!

Would love to see the build thread and pics of this ride!
 
Great Tip!

It is important when tightening these lower bolts that you have the arm in it's normal loaded position so that under normal driving circumstances the bushings are not loaded.

Dave: great tip . . . thanks.
Based on what was said here, and due to the difficulty of pulling the knuckle to press the bushings out and then in, I've decided to only lube up the upper control arm bushings on the frame side only and see if this does it.
Again, thanks for the compliments!
Here's a couple of pics of the finished product. Two and a half year build and I loved every minute of it.
Thanks
Matt
 

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Nice car. The rolled metal sleeves on the bushings is the only part that should rub agains the rest of the poly bushing. I have them on my car and when cold I get some noise. Taking them out and lubing with the proper grease will help.
drilling and tapping for grease fitting will help for future service.
 
Hurricane cobra,

The original owners of Hurricane Motorsports live in my neighborhood.

I've seen this car many of times running around the neighborhood.

introcarlarge.jpg
 
Hurricane cobra,

The original owners of Hurricane Motorsports live in my neighborhood.

I've seen this car many of times running around the neighborhood.

introcarlarge.jpg

Tell Mike and Rich that Matt (HM# 1053) said "hey"! I visited Lee's Summitt before I bought my kit and their honesty and integrity was key in my decision in buying a Hurricane cobra.
And ask Mike when he's gonna get off his buttocks and start building #1100?
He kept one for himself when he and Rich sold the company.;)
Matt
 
Tell Mike and Rich that Matt (HM# 1053) said "hey"! I visited Lee's Summitt before I bought my kit and their honesty and integrity was key in my decision in buying a Hurricane cobra.
And ask Mike when he's gonna get off his buttocks and start building #1100?
He kept one for himself when he and Rich sold the company.;)
Matt

I don't really know Matt all that well but Rich and I have talked from time to time. I know him a little better because his one daughter is the same age as my daughter and they go to the same school and were in Girl Scouts together. Anyway, it was just a little trivia information for you.
 
Found the squeak!

Turns out it was the poly bushings on the frame side of my upper contro arms. Once I had it free from the knuckle/hub assembly, when I moved it up and down it squeaked liked like an old iron gate.
After discovering the source, I didn't pull the bushings from the knuckle (fortunatley), I just coated the outside of the three bushings and slide the control arms back on.
Thanks for the help and all the great info on this forum.
Matt
 
Turns out it was the poly bushings on the frame side of my upper contro arms. Once I had it free from the knuckle/hub assembly, when I moved it up and down it squeaked liked like an old iron gate.
After discovering the source, I didn't pull the bushings from the knuckle (fortunatley), I just coated the outside of the three bushings and slide the control arms back on.
Thanks for the help and all the great info on this forum.
Matt

Hence whay I do not like POLY bushings!
 
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