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Discussion Starter #1
Hello Everyone. I have pretty much totally rebuilt my rear axle assembly. I installed Moser axles (brand new from Moser Website) into a Trutrac by Eaton Differential (axles are clipped and locked in).

*I have after market drilled and slotted rotors that came with the car. I had them turned at Napa Autoparts. One rotors measured thickness is on the maximum thickness size as per factory service manual Maximum and Minimum tolerance. The other sides rotor is about .020 smaller if I remember. However this happened is beyond me. The rotors differed before I had taken them to be turned so I’m not sure if the rotors we’re equal thickness new or if they somehow wore differently. Napa didn’t bother to take the one down to match the other. Anyway, with all this information stated, I need to know this:

Question: What feeler guage thickness in thousandths of an inch is a good safe clearance gap I should have between the 2 brake pads and rotor?

Notes: 1. My Caliper pistons (All rebuilt) are pushed in the caliper totally to their maximum-meaning brakes “not” pressed if you will. 2 I tightened 3 lug nuts onto the face of the rotor to square the rotor against the face of the axle. 3 My brand new Autozone (lifetime) pads may be slightly thicker than other brands-as I had to belt sand some material off each pad-about .010 each to get one caliper to fit over the Napa finished rotor that was on the high end of the FSM thickness tolerance.

My point of question here again: How much feeler space should be between the pads and rotor? I have them to where they are not tight but they “do” rub slightly on the rotor naturally as the pads are just held in there by that cheap spring on the pads and that H clip slider thing. What I’m saying is I can force the pad away from the rotor but when I release the pad falls back on the rotor. (Axles are locked in, brake brackets tight, rotors tightened against axle faces, caliper pistons opened all the way)

Any input here Is much appreciated. I’d hate to warp my newly turned rotors. I’ll be searching the book for any information. .....Thanks
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If I understand your question correctly ,you are Ok.
As long as with the piston fully retracted, the pads have any clearance that is OK.
Hot rotor growth is negligible on a,street car.
Also make sure the sliders and pins move enough for axle in and out movement.
That is to say the pads should both still be able to be loose when the axle is pushed in or pulled out.
Once the brakes are bled and stroked out, the caliper will center and the pads will stay out at the rotor.
Touching, dragging slightly but not binding from lack of clearance.
 

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If you had to remove ANY material for the caliper to be installed you either have the wrong pads or the wrong calipers or calipers that were rebuilt using the wrong pistons for the application.
 

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Discussion Starter #4
Thanks for the reply’s as they always help. As a general answer, I cracked loose the guide pin bolts and that seemed to maybe free up some space. I think tightening the guide pins (which I did also not finalized with thread locker because I’m not ready) while the brake bracket is not slid all the way onto the pins results in pins that may “snag” because they are off center “if you will” in each of their respective functions. I also noticed looking through the manual that I did “not“ have the insulator plates on my “new” pad exchanges from the parts store. This does take up more space. I want all my parts that the FSM book states so I got some pads “with” the insulator shims-both sides. The new insulator shims on these measure about (.023). Thats .046 total. So we will see. Also, my photo I included shows my rotor measuring about (.7865). The book says maximum .787. These have been turned so they came out the box thick. All these things may vary by brand just to be clear. And, I’m going to go ahead and see how these new pads go on. I shall return.
 

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Discussion Starter #5 (Edited)
More info: As I said before, I belt sanded about .010 off “each“ pad (left and right of 1 rotor). Now comparing one pads design to another, the thickness matches. They are both new Autozone. The newer black ones also have a groove splitting the center with a end tapered pad. Anyone know what the benefits of the tapered pad end are? Are they a better pad? Also the slider spring is chromed of some sort (better sliding action) which I think may be an improvement over the dull spring on the left pad. Also, the big difference is one set has shim insulators and both match in size thickness.
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Discussion Starter #6
The side with no brake assembly moves in and out about (.025-.027) with my indicator. The other assembled side moves the same now. The rotor also spins freely With the axle pushed in or out. I think I’m good now.
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