stiff brake pedal/no brakes

[97stoker350]

When I'm driving and hit the brakes one time they work fine smooth braking and everything but if I let off and push them again they will not stop the truck unless you stand on the pedal and even then it doesn't slow down the best

 

[Biggreen96]

Check your vacuum pump sounds like its on the way out . Do our heater controls work? If not then the pump is your problem.

 

[Patrick Feeley]

I would check the vacuum pump. Does your "Brake" light on the dash come on or start glowing? Cheers!

 

[97stoker350]

No light but the foot fan is on wen the knob is in the off position if that has anything to do with it?

 

[DMDP]

Check the vacuum at pump itself. Think it's supposed to be near 25 psi or whatever the measurement of vacuum

 

[Patrick Feeley]

The specification is 17-21 in-Hg when running at normal operating temperature. Cheers!

 

[97stoker350]

I never noticed it before but It does throw a brake light wen u pump on the brakes which is when the pedal gets hard

 

[Biggreen96]

Yeah pump is going out on you. Time to change it out

 

[old man dave]

Don't forget that when you install the pulley back onto the replacement pump, you have to have the mounting bolts back in the holes since you can't get them back in with the pulley installed.

 

[97stoker350]

Thanks for the help guys!!