Help asap with brake vibration

[sandawgk5]

I posted in the bottom of an old thread and it is not getting much action so I will start a new one. I installed Hydro-boost and I am having bad vibrations when I step on the brakes. It acts as if the front wants to leave the truck. Kinda like DW but only when the brakes are pushed. I have notched and bored the orifice on the pump. The rotors are within .001 on runout. What are some possible causes. Is my booster bad? I need help asap as this is the last thing to get the rig back on the road.

Thanks

Ira

 

[MTBLAZER89]

alignment maybe? What's the toe in set at. Maybe under braking the forces are different. I don't know maybe an idea?

 

[sandawgk5]

That is one thing I forgot to post. We measured it with a tape and it appears to be toed out about 1/2" I think it should be toed in and nowhere near that much of a difference.

Ira

 

[chevy9534]

Have you tried turning the rotors. We get alot of vibrations at work with warped rotors. Its a cheap fix.

 

[sandawgk5]

Rotors are not warped I miked them today and the runout is .001

Ira

 

[MTBLAZER89]

That is one thing I forgot to post. We measured it with a tape and it appears to be toed out about 1/2" I think it should be toed in and nowhere near that much of a difference.

Ira

Toe should be about 1/8" toe in.

 

[sandawgk5]

Will excessive toe out cause vibrations while under braking? It is kinda darty which backs up out measurement but can this also be causing my braking problem?

Ira

 

[MTBLAZER89]

I think it might. I would think you would have some wobble just under normal driving with it out that much.

 

[sandawgk5]

I have quite a bit of preload on my kingpins that may be keeping it from vibrating until the brakes start fighting each other. I guess I ought to adjust the toe and take it out again.

Ira

 

[MTBLAZER89]

worth a shot. It's something simple to try. With all the brake stuff being "newer" it almost has to be something with alignment I would think.


Are me and you the only two people posting in the garage Just your two posts staying on top The Navy pays me big bucks to sit here at night and troubleshoot CK5 problems

 

[sandawgk5]

I do my ck5 troubleshooting during the day mostly. Not anything good on TV. The booster I got from a Junkyard with the master cylinder. The brakes work REALLY good other than the vibration. I hope it is not the booster goin out.

Ira

 

[MTBLAZER89]

yeah I work nights in QA so pretty slow usually. I do my own truck stuff during the day/mornings. I don't know squat about HB so I can't help ya there, but try the toe, and see what happens. It should prolly come in anyway so ya don't wear your tires out and have to get new ones or maybe I should toe mine out

"I don't know honey they just wore out fast. I guess we better order those 42's"

 

[sandawgk5]

yeah I work nights in QA so pretty slow usually. I do my own truck stuff during the day/mornings. I don't know squat about HB so I can't help ya there, but try the toe, and see what happens. It should prolly come in anyway so ya don't wear your tires out and have to get new ones or maybe I should toe mine out

"I don't know honey they just wore out fast. I guess we better order those 42's"

If it were only that easy.

Ira

 

[Blue85]

Rotors are not warped I miked them today and the runout is .001

Ira

How are you measuring runout?

Are you saying that the brakes were smooth, then you changed your booster to a hydro unit and now the brakes pulsate? I'm not familiar enough with hydroboost to know what happens if you have air in the system.

 

[sandawgk5]

How are you measuring runout?

Are you saying that the brakes were smooth, then you changed your booster to a hydro unit and now the brakes pulsate? I'm not familiar enough with hydroboost to know what happens if you have air in the system.

I used my mag base and put the mic in contact with the rotor and turned the rotor slowly while looking at the dial indicator. It read .000-.001 while I turned it.

Ira