Brakes

[93fordturbo]

My truck has brake problems. I start the truck up and when i back up out of a parking spot, the brake pedal goes only about a third the way or less and its hard as a rock. It slows the truck down but definately in no hurry. When i rev it up, only sometimes do the brakes work decent. Only decent though. they never are working up to par and sometimes it is dangerous. I cant stop sometimes. I mean it will stop but at 20 miles an hour i can push the brakes down to the floor and it will stop maybe in 30 feet or more. It takes a while. Sometimes the brakes are hard and sometimes they will go down to the floor almost. i took the line running from the pump to the brake boost and at idle i was getting some suction. So whats the problem guys? do i need a new booster or what. What is this i hear about a hydro boost too. thanks a bunch guys. I appreciate it.

 

[Worstenemy453]

why are you only getting 12.6 mpg ?

I believe there is a hydroboost write up in the tech articles section, ill try to find a link.


http://www.oilburners.net/forums/showthread.php?t=8777

 

[gatorman21218]

Sounds like a vacuum pump problem. Check all the lines to the hvac system and cruise and auto trans. If youve got one put a gauge on it. should be pulling 20 inches/hg at idle. I would replace the vacuum pump first then think about hydro boost if the truck is your daily driver

 

[sassyrel]

My truck has brake problems. I start the truck up and when i back up out of a parking spot, the brake pedal goes only about a third the way or less and its hard as a rock. It slows the truck down but definately in no hurry. When i rev it up, only sometimes do the brakes work decent. Only decent though. they never are working up to par and sometimes it is dangerous. I cant stop sometimes. I mean it will stop but at 20 miles an hour i can push the brakes down to the floor and it will stop maybe in 30 feet or more. It takes a while. Sometimes the brakes are hard and sometimes they will go down to the floor almost. i took the line running from the pump to the brake boost and at idle i was getting some suction. So whats the problem guys? do i need a new booster or what. What is this i hear about a hydro boost too. thanks a bunch guys. I appreciate it.

sounds like the vac pump is about dead--you need to put a gauge on there--

 

[93fordturbo]

why are you only getting 12.6 mpg ?

QUOTE]
To be honest, with all of my idi's i have only got 16 or 17 a few times but averaging about 13 all the time between the three that i have had

 

[Worstenemy453]

why are you only getting 12.6 mpg ?

QUOTE]
To be honest, with all of my idi's i have only got 16 or 17 a few times but averaging about 13 all the time between the three that i have had

I get about 20 depending on how i drive. Maybe my truck is special

 

[gatorman21218]

Gear ratio, IP/injector age, transmission (OD or no OD), timing all play a big part in fuel economy. Also driving style (Mario Andretti vs Mother Terresa), City vs Highway, load or unloaded factor in. There are a lot of variables to consider when comparing fuel economy

 

[93fordturbo]

i have a zf 5 speed and i do like to get where im going rather quickly. I also have 35s and my gears are 4:11 i think

 

[93fordturbo]

i will check my boost later tonight and tell you guys what it is. A mechanic said that it is prolly the boost and not the pump because it was getting suction. I heard that the boost ( or whatever you call it) is spendy. (what is that thing called that the pump sucks air from?)

 

[gatorman21218]

The brake booster. The big circular thing behind the MC

 

[Worstenemy453]

Gear ratio, IP/injector age, transmission (OD or no OD), timing all play a big part in fuel economy. Also driving style (Mario Andretti vs Mother Terresa), City vs Highway, load or unloaded factor in. There are a lot of variables to consider when comparing fuel economy

My IP and injectors are 94,000 miles/24 years old, I have a C6 with no OD, empty with 3.55's i get close to 20 when i drive like i have some sense.

 

[93fordturbo]

my vacuum pump is putting out 12-13 at idle. Bad?

 

[lotzagoodstuff]

Try unplugging the vacuum line to your brake booster and see if you have the same or similar symptoms. Do it someplace safe, with lots of runoff space, but it sounds like it's a vacuum booster issue.

 

[87crewdually]

my vacuum pump is putting out 12-13 at idle. Bad?

If this reading is at the pump then it is out of spec. If your reading was at the booster and when you test vacuum at the pump and it's say 21, then you have a leak somewhere. Unplug hoses at the manifold on the passenger side firewall and check each line with a vacuum pump to make sure they all hold vacuum. Also if you have cruise check the metal can on the driver-side, they tend to rust out causing a vacuum leak.

 

[93fordturbo]

I unplugged the hose right where it hooks into the booster, (that round thing) and got 12 to 13 psi. When i reved it up, it went to 25 or more. I also hear a whooshing sound when i unplug the hose from the booster... Idk?