Minor brake problem when starting up truck

Ok ill try to explain as good as i can. Ever sense i bought my truck. it has had a braking problem, not too big of a problem but it has gotten annoying, every morning when i have let it idle for awhile and i get in and take off when i apply the brakes for the first time for some reason the truck barley stops having the peddle all the way down. But after a few pumps and the more the truck gets warmer, it starts braking better and better. i really don't know what could be the problem, brakes are good, fluid is good, and everything, it just happens when the truck hasn't been moved for awhile or its cold. if anybody has had this problem let me know, and i hope im making sense. I'm also wondering if it might be the brake booster. and it has to be replaced. but might be wrong.

 

could be that or master cylinder, i'd start with those.

 

Ya...... Ill see if I can find one and swap it

 

Could also be sticking calipers, that loosen up at they get warm.

 

Id go with the master cyl too.. Air could be accumulating and then worked out as you pump the brakes

 

I have the same problem as well. I was told by a reputable shop that it could be the check valve in the booster vac hose that is sticky from moisture in the line.

 

mmm ill check the vacuum hose and if its not that then ill see if i can replace it for another one, also everytime i step on the gas theres a noise coming from the firewall driver side. sense i got it, ive also been wondering if its the booster.

 

If it was the booster, it would be a constant no brake. Do you have a vacuum tester? If so, hook it up to the booster and check for leakdown. What kind of noise is it? Rattle, squeak, whoosh?

 

have you ever heard a longboard or a skate board when the brearings have no more lube and it sounds like the ball bearings are just rolling dry with metal to metal. it sounds like that, ill have to record it cause thats the best i can explain it. its only when the car is going and at a high RPM, its not the suspension, just incase someone says its the wheel bearing, and it couldn't be my supercharger.

 

A low rumble grinding sound? Kind of deadened too? Can't help you there, but if it sounds like a bearing it most likely is. I don't have too much experience with these trucks yet (1 mo.) just mechanics in general.

 

i would say a vacuum issue

 

ill try to record it today and post it up but im pretty sure its the booster

 

After reading your posts again and thinking some more, I'm leaning towards a vac issue too. I haven't heard anything from my truck yet, just the hard brake at start up.

 

heres a video of the braking and noise. actually the braking problem was a little better then usual, and almost at the end i meant to say brake pads not calipers but you can clearly here the grinding noise. it sounds like its coming off the supercharger but its not. cause if im in the freeway it does it aswell when the S/C is not running at a high RPM and when im just going at a slow steady speed it doesnt make the noise.

http://www.youtube.com/watch?v=G_wBDi-fanY&feature=g-upl

 

Take a look at that booster. The diaphragm may be split.

 

can you take it apart ???

 

It was put together, it can be taken apart, but I'm not recommending it. Brakes are some serious stuff. I don't recall a rebuild kit for one either. And I'm sorry, I should have been more clear in my last post... I should've said for you to get the booster vacuum tested, that's what I meant by "taking a look" at it. My bad.

 

haha alright ill look for another one and swap it, i can find one for pretty cheap thanks