DREYKO

that do you think, i can slowly push em to the floor but if you push em real fast it'll catch instantly
thats the deal, im not loosing fluid and ive bleed the fronts so it shouldnt be air

BLKTOPTRVL

You have a leak or air in the system. If you can't bleed it out, rebuild/replace the cylinders.

DiverseCC

could be the master cylinder too

IaMtHeRuThLeSs1

mine was doing this exact thing.

It was the brake master cylinder...really easy to replace.

90WhiteVrt

Yeah my guess is its the brake master cylinder. You can get a replacement for around $40. The only difficult part about the change is moving over the resevior to the new master cylinder.

Syonyk

Third or 4th the "Brake master cylinder" diagnosis. Mine was doing that exact same thing last time it got cold out, but not leaking any significant amount of brake fluid (it waited until it was well below zero outside to actually start leaking). I replaced the master cylinder and it fixed it, 100%.

-=Russ=-

Go48

iTrader: (7)

Check the vacuum brake booster according to the instructions in the factory service manual. That sounds like the problem you're describing, especially the "instant catch" you describe.