3500 mile trip. With a brake problem?



I just completed a 3500+ trip to Fl. from Ct. What a trip!!!! Had a ton of fun with the top down. Now for the problem. I had to jump on the brakes at 60 mph and the front end went side to side untill the car got down to about 40mph. and then it stoped in a straight line. I have added pbb and rebuilt the drum brakes before I left. I didn't replace the direction valve, could that be it? I check the brake adjustment and it should be right.
Thanks for the help Jim
I had a problem with my front brakes this year. The problem I had never heard of before. I my have shared my story in the earlier forum.

Long story short, the hydraulic lines from the body to the slave was acting like a check valve because it was almost blocked. With the hydraulic pressure from hitting the break was high enough to give me breaking but the spring in the slave was not strong enough to release the pressure to the shoes.

Make sure the lines are clear. You may have one that is blocked? I had to completely remove the line and use air pressure to identify the blockage.

Good luck, Ric.
Could be rotors or drums are warped from incorrect tightening sequence or over tightening.

Also make sure you have no air in the lines... a good bleeding will do it.

If you don't change your fluid regularly... every year or 2, the brake fluid picks up moisture from the air and you could have a caliper or piston freezing up from rust.

Also old rubber brakes lines can swell under pressure.... 30 year old rubber may not be as strong as it used to be.
8) first thing to check is brake adjustment. next check the lower control arm bushings, when they go bad they cause a number of problems inclunding the one you describe.
Check that brake adjustment. Also lets not forget. Four wheel drum brakes stop alot different than lets say more modern systems. ;)
RB is on the money, IMO. BUT... check and replace those flex lines. I know of a life wasted last year when old flex lines suddenly gave way, on a single brake system. Dual brakes are something to strongly consider.