How do I tell if I have the JB7 brake option ?

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Goldie Driver

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Morning !

Based on the picture from the parts website, the caliper sure looks like a JB7 , although my bleeder screw sticks straight up :

https://www.autozone.com/brakes-and-traction-control/brake-caliper-front

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I do not see anything on the service parts sticker, so I am puzzled as to how to know for sure.

Thanks in advance !

Britt
 
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Blue Ox

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Look at the rear drums. If they're 13 inches it's a JB7. JB6s have 11 inch drums.

If this is for the K1500 in your profile it does not have a JB7. Only 2500s would have had it.
 
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Goldie Driver

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That is cool info - thanks ! I will have to look, but can you tell by the shoe size ? Mine were 11.16" by 2.75".

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Blue Ox

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11" vs 13" does refer to the shoe size/drum ID. Actually 11-5/32". I rounded.
 

Goldie Driver

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Sooo - bought 18-4124 caliper from Advance Auto for the PS and 18-4125 for the D'S.

Tried the PS - looks exactly like the old except the inboard ears are slightly thicker.

Fits right in the spot with no pads - add pads and no go on.

I have not tried the DS.

I did try compressing the piston- no go.

I assume somehow some way it is wrong - anyone else run into this?

Those numbers are for the JB5 & 6 option - good call/info from Blue Ox.

TIA !

Britt
 

Goldie Driver

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Well, whatever it was, the new one they ordered fit perfectly.
Got both sides done tonight after work.

Now, on to more projects ...

:happy160:
 

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