rotor runout

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Apr 1, 2011 | 01:05 PM

fugawi

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Melting Slicks

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From: westmoreland N.H.

rotor runout

i've got new calipers with o ring seals. what is an acceptable runout. right now i've got .008 on both sides.

Apr 1, 2011 | 01:52 PM

Richard454

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From: Fernandina Beach FL

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Acceptable?

Supposedly -what I have heard/read from the factory was .008...

However- while you are at it....have it on jackstands... the caliper's off- Why not shoot for .002? Beer cans- Diet Coke cans in my case work well and will just cost you another hour or so...

Richard

Apr 1, 2011 | 09:43 PM

72LS1Vette

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From: North Easton Mass

The O-ring seals aren't as sensitive to runout as the lip seals are. Lip seals will let air pump into the system with excessive runout but I don't think O-ring seals have the same issue.

You might want to look on the VB&P website or ask whoever you bought the O-ring seals from.

Rick B.

Apr 1, 2011 | 11:15 PM

redvetracr

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From: WI

.003 max

Apr 2, 2011 | 06:10 AM

baxsom

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From: Rockledge FL

Quote:

Originally Posted by redvetracr

.003 max

i thought it was .05. maybe that was for O rings. anywho, there are many people on here that use the O ring calipers, never check the runout and never have a problem.

I have read a lot on here about shimming. The only thing I cant find is where to put the shim. Does it go on the high or low spot?

Last edited by baxsom; Apr 2, 2011 at 06:47 AM.

Apr 2, 2011 | 09:56 AM

Mike Ward

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.008" is the most commonly quoted maximum. If it's causing you not to sleep well, fix it.

Apr 2, 2011 | 11:53 AM

fugawi

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Melting Slicks

Joined: Jun 2004

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From: westmoreland N.H.

thanks everyone. looks like it'll be just fine the way they are.

if any problems i know what to do.

Apr 6, 2011 | 08:30 PM

gcusmano74

Drifting

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Stainless Steel Brake Co in NY used to sell a shim for exactly that. It was drilled for the wheel studs and covered the whole hub. The factory spec for runout is very small. If you have the O ring type caliper seals they will tolerate a bit more. To try to reduce the runout, first I would pull the rotor off the hub and (1) clean it up nice, and then, if that doesn't help, 2) try repositioning it on the hub. You could also bring it to a brake shop and have them cut it, but then you will have a "thin" rotor.