anyone need the part number for1 ton Master cylinder to fit K5\'s I just swapped out my stock Master cylinder on my '79 K5 for one for a '79 K30, I work for Autozone, so I had a chance to compare all the cylinders to find the right one. The 1 ton cylinder has a noticeably larger piston and better fluid capacity. The only major difference from the stock one is the front/rear reservoir locations, the 1 ton is reversed. I just did a little careful massaging of my lines where they hook to the cylinder and swapped thier connection location. The fittings are the same size and the differnce in stopping power is night and day, no more having to force the pedal to get a hard stop, now just steady pressure and she stops great. The company is Fenco(autozone brand) part # M1584, and NM1584 for a new one. Most Autozones or parts stores should stock the reman, new one is special order. The prices are reman=$17.99+$18.00 core, just take your stock one back and $92.99 for the new one, both have a Lifetime warranty /forums/images/graemlins/thumb.gif Krennen Oh! BTW, this should fit any K5 with power brakes and a solid cast iron master cylinder. "KEYWORD" should, not sure about newer years, but olders I am sure of.