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**jocko** · 11-19-2018, 10:27 PM

3/4 ton and 1/2 ton mc's are not the same. On a 3/4 ton mc in 71 (I assume this is for your 71?), the forward port is for the rear brakes and the rear port is for the front brakes - opposite of the 1/2 ton mc. Yes, the 1/2 ton mc is more intuitive, but that's what ol uncle GM did. You need to specify 1/2 vs. 3/4 ton as well as power or manual when buying to make sure you get the correct one.

11-19-2018, 10:27 PM	#6
jocko Senior Member Join Date: Oct 2009 Location: Godley, TX Posts: 18,001	Re: Power Master Cylinder 3/4 ton and 1/2 ton mc's are not the same. On a 3/4 ton mc in 71 (I assume this is for your 71?), the forward port is for the rear brakes and the rear port is for the front brakes - opposite of the 1/2 ton mc. Yes, the 1/2 ton mc is more intuitive, but that's what ol uncle GM did. You need to specify 1/2 vs. 3/4 ton as well as power or manual when buying to make sure you get the correct one.