93nissanpuman

I have a 93 nissan pickup,4cylinder, 2 wheel drive standard pickup I bought new in 93 it now has 184,000+ miles on it, in January I started having trouble with the brakes, the booster, master cylinder, proportioning vavle, check valve drawing vacuum from the engine, have all been changed, turned the rotors yesterday put new pads and shoes on it drove fine after but this morning it drove as if I had the brake on even though I didn't, the pads smoke because of the pressure andI am at wits end as what to do next even nissan America has no clue, I would appreciate any information on the above mentioned, thanks and it is much appreciated!