Brake Lock Up

[86454]

Very strange but when I first start up my 86' 2500 and put her in gear, if I even so lightly step on the brakes, the wheels lock up.

She has an electric choke and when first started the engine races until warmed up.

After she warms up, I don't have the brake issue.

It seems to happen when it's wet/humid outside more often than when dry.

What the heck could be causing that?

 

[samry]

Probably just rust built up on the rotors and drums from sitting over night, iI assume that after you drive it a little bit it doesn't do it anymore. Thats why on humid days it seems to do it and not so much on dry days. Cheers

 

[86454]

Probably just rust built up on the rotors and drums from sitting over night, iI assume that after you drive it a little bit it doesn't do it anymore. Thats why on humid days it seems to do it and not so much on dry days. Cheers

Yes, actually after paying closer attention, you are right. Humid / Wet days make it worse. Dry days, no lock up...

 

[ISLANDER914]

I had an 88 suburban, a 78 caprice and even my 99 does that. I always thought it was the higher engine rpms creating better vacuum for the brakes that did it. It still drives my wife nuts rolling out of the driveway and I hit the brakes. She always asks "why do you have to jam on the brakes in the driveway". Makes me laugh every time.