Rear Brake Cylinder size

[cthudak]

Hi, Does anyone have an easy way to know which size / bore I might have on my rear drum brake cylinders. Napa and Raybestos offers 2 bore sizes 3/4" or 13/16". I have 10" dums......any help, thanks

 

[RangerX]

If you're talking about a Ranger, I'd bet that the smaller size is for a 7.5 axle, and the larger for an 8.8.