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Prothane Bushings Shredded

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Wow, that's seriously chewed up. The inner part of the bushing got pulled out from between the sleeve and control arm and twisted like an orange peel.

Where did you grease the bushing - between the sleeve and bushing, or bushing and arm? The bushing is supposed to rotate on the sleeve, so the bushing and arm rotate as one unit. The grease goes on the ouside of the sleeve / inside of the bushing.

Is the sleeve long enough? The sleeve should protrude slightly from the bushing ends, so torquing the bolt clamps the sleeve, not the bushing.

Are the areas where the bushing ends contact the body-side bracket smooth?

This looks like the sleeve may have been a bit short, and torquing the bolt caused the end of the bushing to be stuck against some sawtooth-like protusion on the mounting bracket. Every suspension movement caused the bushing to rotate and ratchet against the protrusion, which peeled the bushing out little by little. Just my guess looking at the pics.
Dave, I just did a little clean up of the pocket in the k member, there is no offending metal shards or random weld flash. Also I pulled out the forward bushing that got orange peeled. The complete front bushing is present, not a bunch of pieces.

Excuse any redundancy but I attached the instructions. As I read these, the bushing and outside surface of the sleeve get grease. I used the correct Prothane urethane grease and didn’t spare any (too much?).

The end surface of the sleeve shows some wear marks probably from rotating and maybe torque of the bolt. I did torque the all 3 LCA bolts to 129 ft lbs..

IMG_4734.jpeg

IMG_4735.jpeg
 
Wow, that's seriously chewed up. The inner part of the bushing got pulled out from between the sleeve and control arm and twisted like an orange peel.

Where did you grease the bushing - between the sleeve and bushing, or bushing and arm? The bushing is supposed to rotate on the sleeve, so the bushing and arm rotate as one unit. The grease goes on the ouside of the sleeve / inside of the bushing.

Is the sleeve long enough? The sleeve should protrude slightly from the bushing ends, so torquing the bolt clamps the sleeve, not the bushing.

Are the areas where the bushing ends contact the body-side bracket smooth?

This looks like the sleeve may have been a bit short, and torquing the bolt caused the end of the bushing to be stuck against some sawtooth-like protusion on the mounting bracket. Every suspension movement caused the bushing to rotate and ratchet against the protrusion, which peeled the bushing out little by little. Just my guess looking at the pics.
One more pic. I took out the sleeve and rear bushing, without much resistance. The rear bushing is damaged as well, you can see the cracks along the body going to the shoulder.

PSA, if using these you might want to take a closer look.

IMG_4736.jpeg
 
139
245
Exp. Type
HPDE
Exp. Level
3-5 Years
Central Florida
I have not removed the passenger side yet. I am ordering the delrin set up from Kohr so soon I will know how the RT side did. Dean suggested make the delrin change as these urethane bushings will fail again.
Do you have a link for these? It’s an upgrade I’ve been considering
Thanks
 
Just to confirm the Boss S Delrin bushings fit into the 2011-2014 oem lower control arms?
Yes that is how i understand it. Someone else may correct me but…I believe all 2011-2014 front lower control arms base part are the same even on Boss S (R?). The difference in part numbers reflects installed ball joints.
 
Dumb question, given how much work the Ford and Multimatic guys did with the stock front fluid bushing (i remember watching them go through the pain) is the upgrade to delrin worth it? does the steering feel change that much or is it something else?
 
Dumb question, given how much work the Ford and Multimatic guys did with the stock front fluid bushing (i remember watching them go through the pain) is the upgrade to delrin worth it? does the steering feel change that much or is it something else?
In my situation, the rear OE bushing had cracked, due to age and normal use I assume. Urethane was the semi universal upgrade from factory pieces. As the pics show it didnt go well for me.

At this point I could put new urethane back in and monitor closely or go to the racer’s solution, delrin. I certainly won’t torture the car like a campaigning race team but those are the choices.
 
1,291
1,296
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
I was under my car changing the oil today and checked the front bushings. Mine still look good. I wonder what caused the failure on yours?
 
I was under my car changing the oil today and checked the front bushings. Mine still look good. I wonder what caused the failure on yours?
That’s good there is no damage on yours.

I could have installed them incorrectly but other than front and rear assignment by part number, not much can be installed wrong. They had lots of correct grease and torqued to 129 fr lbs.

It has been suggested that the more restrictive rear urethane bushing causes the front to fail. However yours hasn’t failed.

I still have a choice between urethane and delrin and the urethane parts are sitting here, delrin has no delivery date yet.
 
1,291
1,296
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
I did not use the Prothane grease. I always use RedLine Synthetic on poly bushings and have never had a problem. I don't remember what the torque spec was when i installed them. I do have a set of the Ford Performance deleon bushings waiting to go in when these fail. Did you check with Capaldi on the delrin set? They are pretty close to you.
 
I did not use the Prothane grease. I always use RedLine Synthetic on poly bushings and have never had a problem. I don't remember what the torque spec was when i installed them. I do have a set of the Ford Performance deleon bushings waiting to go in when these fail. Did you check with Capaldi on the delrin set? They are pretty close to you.
I ordered from Kohr. Order was entered on July 3 so the long weekend is in play. I am guessing these Ford Performance parts actually get shipped from Livonia MI where the FP warehouse is located. At least that is how other FP parts came to me when ordered through Kohr.
 
139
245
Exp. Type
HPDE
Exp. Level
3-5 Years
Central Florida
Does anyone know if I can use the ford performance bushings M-5638-C in the 11-14 oem lower control arms and the oem ball joint?

I know the boss s arms had extended ball joints but they seem like an extra place for failure.

Car is lowered an inch and I don’t have any bump steer issues
Thanks
 
One more pic. I took out the sleeve and rear bushing, without much resistance. The rear bushing is damaged as well, you can see the cracks along the body going to the shoulder.

PSA, if using these you might want to take a closer look.

View attachment 96691
*Update* I had a conversation with Prothane tech support. This type of failure has not been seen with such low mileage even with HPDE track events. This is now the second supplier with the same reaction. Prothane is the manufacturer.

All things considered, I put the new replacement Prothane bushings on and reinstalled the LCA. It was the least amount of work for me and I have new springs, struts camber plates that need to get to the test and tune next week.. Delrin pieces are ordered and that may become a winter project.
 
1,291
1,296
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
*Update* I had a conversation with Prothane tech support. This type of failure has not been seen with such low mileage even with HPDE track events. This is now the second supplier with the same reaction. Prothane is the manufacturer.

All things considered, I put the new replacement Prothane bushings on and reinstalled the LCA. It was the least amount of work for me and I have new springs, struts camber plates that need to get to the test and tune next week.. Delrin pieces are ordered and that may become a winter project.
Let us know how this set holds up.
 

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