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Trunnion pin diameter

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Bremer

Bremer

Jedi Hopeful
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Hi, I ran into an unexpected problem during the reassembly of my 59 TR3A front suspension. I obtained two good used trunnions as the originals had a lot of play in the connections with the vertical links. All these trunnions are zero castor. The left side went together no problem. On the right, the wishbone won't fit over the pin (shaft). I measured the pin at 15.85mm max, while the bushing in the wishbone is about 15.70mm. You can imagine I was quite surprised to see this. Would it be better to ream the bushing to the pin or should I reduce the diameter of the pin?
By the way, any idea why the factory did this? Certainly not just to annoy people...
Thanks for your responses.
 
15.85 = 0.624"...The pins are supposed to be 5/8", so that dimension is correct. When new bushings are installed, they are smaller in diameter so they can be reamed to fit the pins.

Production tolerances often don't allow for precise fits, so bushings are often made to be sized after installation. We do it everyday here at work with the bushings in starter motors. We don't use reamers however, we use roller burnishers...and we roller burnish every bushing that gets installed.
 
Thanks for your responses. I'll ream the bushings to size.
 
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