Red or Black Body Bushings

[pontiacgp]

GM ought to have put the rubber bushings in a sealed bags to prevent oxygen from degrading the rubber....

 

[joesregalproject]

Going from my own experience, every rubber body bushing in my car had rusted inserts. They were all seperating from the rubber and in much poorer shape than the rubber itself. One of my old bushings the insert was gone, rusted completely away taking the frame mount with it, but the bushing still looked fine from the outside, no cracks or splits. At least for me, the molded in inserts were the most deteriorated part of my old bushings. It is a very known fact that rust spreads from bad metal to infect good metal, that is how it creeps under paint and other coatings. IE, rust spreads from the inserts to the frame mounts since they are in direct contact. Researching body bushing replacement online, I have seen that every posted photo of old rubber bushings shows them having rusting inserts seperating from the rubber. Many have posted about a pile of rust coming out of the old bushings when they are removed. It seems to be a pretty common phenomenon going by all the postings online about body bushing replacement showing rusting inserts and . Perhaps Energy Suspension rust proof their inserts better than GM did, but I didn't want to take the chance and choose bushings without inserts. Here is one post about a Ford Explorer body bushing hardware rusting out http://www.explorerforum.com/forums/showthread.php?t=292471&page=2 Here is another example of rusty bushing inserts in a Jeep, http://www.jeepforum.com/forum/f8/kens-1985-cj7-refurbishment-thread-1040550/index102.html.

I do not know if that model number of Enegry Suspension bushings are polygraphite bushings, it was a general remark about polygrapite bushings. Not all black poly bushings have graphite, but I guess some brands may use color to denote if they are polygraphite or regular poly. I have seen red poly bushings with graphite swirls in it. My black poly bushings don't contain graphite.

I agree that the factory inserts rust out but I disagree that rust is contagious and that the rust from the insert spreads to the frame. I rather think water sits around the bushing and causes the frame and insert to rust, but the rusting of the frame starts at the frame and the rusting of the insert starts at the insert. Also I do not believe that poly alone is strong enough to support the weight of the body over time without an insert and that is why I went with the Energy Suspension kit. And yes the Energy kit's hardware is all zinc plated.

Personally I believe that even if these inserts do rust out, by the time they do, the solid poly bushings without an insert would have worn out and/or collapsed on themselves without an insert supporting them.

 

[Clone TIE Pilot]

Going from my own experience, every rubber body bushing in my car had rusted inserts. They were all seperating from the rubber and in much poorer shape than the rubber itself. One of my old bushings the insert was gone, rusted completely away taking the frame mount with it, but the bushing still looked fine from the outside, no cracks or splits. At least for me, the molded in inserts were the most deteriorated part of my old bushings. It is a very known fact that rust spreads from bad metal to infect good metal, that is how it creeps under paint and other coatings. IE, rust spreads from the inserts to the frame mounts since they are in direct contact. Researching body bushing replacement online, I have seen that every posted photo of old rubber bushings shows them having rusting inserts seperating from the rubber. Many have posted about a pile of rust coming out of the old bushings when they are removed. It seems to be a pretty common phenomenon going by all the postings online about body bushing replacement showing rusting inserts and . Perhaps Energy Suspension rust proof their inserts better than GM did, but I didn't want to take the chance and choose bushings without inserts. Here is one post about a Ford Explorer body bushing hardware rusting out http://www.explorerforum.com/forums/showthread.php?t=292471&page=2 Here is another example of rusty bushing inserts in a Jeep, http://www.jeepforum.com/forum/f8/kens-1985-cj7-refurbishment-thread-1040550/index102.html.

I do not know if that model number of Enegry Suspension bushings are polygraphite bushings, it was a general remark about polygrapite bushings. Not all black poly bushings have graphite, but I guess some brands may use color to denote if they are polygraphite or regular poly. I have seen red poly bushings with graphite swirls in it. My black poly bushings don't contain graphite.

I agree that the factory inserts rust out but I disagree that rust is contagious and that the rust from the insert spreads to the frame. I rather think water sits around the bushing and causes the frame and insert to rust, but the rusting of the frame starts at the frame and the rusting of the insert starts at the insert. Also I do not believe that poly alone is strong enough to support the weight of the body over time without an insert and that is why I went with the Energy Suspension kit. And yes the Energy kit's hardware is all zinc plated.

Personally I believe that even if these inserts do rust out, by the time they do, the solid poly bushings without an insert would have worn out and/or collapsed on themselves without an insert supporting them.

Rust is a electrochemical process and a rusting piece of metal and iron oxides particles can pull ions out of a healthy piece of metal through conduction by contact. Metals have different degrees of electro-negativity, ion migration due to this difference in electrode potential occurs when the metals are in contact and there is some kind of electolyte present like water, like a weak battery. This is why the passenger side number 2 mount is often the worst shape due to the HVAC drain dumping water on that mount. As I said before, this is the reason guardrails have rubber or wood spacers betwen the rail and steel support posts or all wood support posts. Even through both guardrails and metal support I beam posts are both steel, they are slightly different alloys which leads to different electrode potential. I doubt our car frames and the bushing inserts are identical alloys of steel which would lead to a difference in electrode potential between the two. Water sitting around between the bushing and frame is a big part of the rust problem, that I agree with you.

The body on these cars aren't that heavy, two men can lift a bare body off the frame on a G easy. While molded in inserts can help distribute compressive stress more evenly on the side of the bushing projection being compressed. Unfortunately, it also acts as a stress riser at the top edge of the sleeve where the projection starts, so it precipitates bushing splitting and separation at the top of the projection like my stock rubbers did. The whole issue can be sidestepped with rigid bushings like Derlin. Prothane bushings are a higher durometer than Energy Suspension, making a steel insert unnecessary.