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TR2/3/3A TR3 Trunnion to bushing clearance......

karls59tr

Obi Wan
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I'm taking my bushing and trunnion in to the machine shop to get it reamed but cant find the thread on what the ideal clearance is. I know that 5/8 or .625 is what the bushing should be reamed to but the aftermarket trunnion may not be up to spec. What spec should I tell the machinist to make the bushing to trunnion clearance?
 
I don't recall the numbers offhand, but you should be able to tell him "make it a free-running fit" and he'll know what that means.

But personally, I would not accept a "not up to spec" trunnion, since it is a safety-critical item (holds the front of the car off the road!) and if you can find one obvious defect; there may be more that are not so obvious. IOW, if the pin is too small or large, it may also be too soft or too weak.
 
My machinist fit them to .001". They don't got very hot, so you don't have to worry that the clearance will change while running. He also said, "It'll wear bigger soon enough..."
 
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