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  1. #1

    Default Hard to steer and Poor Braking, HELP!!

    Hello everyone! I just bought a 2003 Silverado 2500 W/T with the 6.0 and auto trans. The guy i bought it from recently had the power steering pump replaced as it was getting hard to steer. Apparently that didn't fix the issue, so he sold it to me.
    I checked for any obvious vacuum leaks and didn't find anything. The issue is that whenever you're driving slowly (or the engine is at idle) it is insanely hard to steer, and the brakes get mushy. The main issue for me is the crazy hard steering. If you give it a little gas the power assist will generally come back. He said it had something to do with the brake booster, that they're somehow linked, i've never seen that, so i'm a bit puzzled.
    Anyone heard of this??? I really want to get this resolved ASAP
    Thanks EVERYONE!!!!!!

    It should also be mentioned, the power steering fluid is not low. It does have a bit of a whine to it when sitting, revving and turning the wheel, nothing ridiculously loud, but certainly present...
    Last edited by riponfrosh; 06-17-2010 at 04:34 PM.

  2. #2
    Sr. Engineer
    Join Date
    May 2009
    Manitowoc, WI


    What rpm does it idle at? My first thought is if there isn't enough vacuum and the power steering only works when you give it a little gas is its idling too low.

  3. #3


    idle was at 1000rpm when i just started it up, couldn't turn wheel... that idle is certainly high enough to maintain proper power steering assist... thanks though!!

  4. #4


    Steering box grinding? joints everywhere okay? Lines clogged up? Try flushing your lines out. Vacuum leaks, basic things to check for.
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  5. #5


    The truck must have HydraBoost power brakes. Steering and braking assist are both from the power steering pump.

    If the pump is OK, there must be some blockage in the lines, steering box, or brake booster preventing flow. I don't know much about them, so I can't offer much more information.
    When you hear hoofbeats, look for horses not zebras.

  6. #6


    It is a hydraboost, at least i think it is at it's different than anything i've seen. The power steering lines run up to where the brake booster "should" be.
    I've been hunting around for vacuum leaks. I've found that if I remove the pcv valve from the valve cover it has NO effect on the idle. maybe that's how these run, but i'm used to that causing the engine to stumble. Same with removing the oil filler cap... removing it has no effect on the idle. Usually the loss of vacuum will cause irradic and poor idle.
    Idle looks like about 600 once it settles down. It runs great other than the power steering/ brake issues.

    EDIT: After looking around, it appears the "hydraboost" system doesn't really run on vacuum at all... so i don't believe a vacuum leak to be the culprit.
    Last edited by riponfrosh; 06-17-2010 at 05:41 PM.

  7. #7


    Quote Originally Posted by riponfrosh View Post
    EDIT: After looking around, it appears the "hydraboost" system doesn't really run on vacuum at all... so i don't believe a vacuum leak to be the culprit.

    I don't think a vacuum leak should be your problem if your brakes are getting mushy that most likely would have something to do with the hydraboost system, also the vacuum leak should not cause the steering to be tight

    sounds like you may have a bad hydraboost component

    2003 Z71 Silverado LS
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    Waiting to be installed
    Two 8in RF HX2 punch( would have 12s but they got stolen)

  8. #8


    Did you ever figure this out? I've been searcing online for days with the exact same problem. If anyone knows what's wrong here please let me know. I have a 96 hydro boost truck with a new hydro boost valve and shop suposedly changed all the lines and tried a new pump and still can't figure out ( they put the old lines and pump back on after new didn't fix but left the new boost valve) It is almost impossible to plow snow with and I need help in the worst way.

    Someone please help.........

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