Trailing Arm Bushings, What material to select? |
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Trailing Arm Bushings, What material to select? |
malcolm2 |
Aug 28 2014, 03:32 PM
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#1
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Advanced Member Group: Members Posts: 2,747 Joined: 31-May 11 From: Nashville Member No.: 13,139 Region Association: South East States |
I need to replace the rear wheel bearings, so "while I am in there" I will also tackle the bushings.
Rubber looks to be the OEM choice but is hard to find with the exception of the elephant racing kit that includes the shafts and install tools. $300+ I used the Elephant bushings on the front. I found poly-graphite to be the least expensive < $20 for a set of 4 bushings only With Delrin as the middle of the road choice. @ $50 for a set of 4 bushings only So what is the +/- of each material? Can you throw a few vendors out there? My car is a daily driver? Clark |
Rob-O |
Sep 22 2014, 02:03 PM
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#2
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Senior Member Group: Members Posts: 1,252 Joined: 5-December 03 From: Mansfield, TX Member No.: 1,419 Region Association: Southwest Region |
I lightly skimmed this thread but thought I'd add this in case it wasn't brought up before. Back in the day when there was nothing but poly and factory (and as far as I remember you couldn't just buy the factory rubber bushings) the trick was to pull the rubber ones out, and then machine all three pieces. The inner shaft, the bushing and the control arm.
My pivot arms were rusted, so after rust removal we welded the shaft and then turned it down on a lathe. Got the measurement precise on the pivot then the bushings inner diameter was machined slightly to fit the pivot arm. The trailing arm was machined as well to get it in round so the bushing would fit correctly. All of the poly bushings had different measurements. Even without a micrometer you could tell that they were different. One would fit perfectly, the next was tight on the same spot on the same trailing arm. The next was loose, and so on. That poly material seemed to swell as it got warm as I recall. It sounds like Chris at Tangerine attacked this issue since he provides a hone to get the trailing arm portion round (assuming I read that correctly). Ultimately, since rubber was used as the initial material, I doubt any of the aftermarket offerings will be perfect right out of the box. Not because they don't make a great product, but because the factory tolerances were never designed for a precise fitting bushing. So, to me (and I worked in the polymers industry for a long, long time) we may be over engineering this problem. As long as you have a good bushing material and machine all four mating surfaces (the trailing arm housing, the bushing outer diameter, the bushing inner diameter and the pivot arm outer diameter), you should be fine and if the material is correct, squeak free. |
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