Help 2003 2500hd power steering brake lockup

I have a 2003 Silverado 2500hd diesel with Allison trans. Long bed crew cab. Truck has32,ooo miles with no other problems other than scheduled oil changes and trans fluid and filter at 30,000miles

Two weeks ago I went out to start it on Monday morning after it sat still from Friday afternoon. When I started it with trans in Park and put it in reverse to back out of the driveway the steering froze and the brakes were impossible to press down. It felt like the hydraulics were gone on both. A tow truck came and the driver finally manhandled it straight enough to be towed to the dealer. At the dealer that afternoon the mechanic started it and everything worked fine so they told me to come get it. This weekend the same thing-it sat still from Friday started on Monday morning and brakes and power steering wouldn't work. I turned it off and tried again -no luck. Then I had an idea. I put it in neutral and started it-everything worked OK. I took it back to Chevy dealer and told them what happened. When I returned the next day they said they couldn't find anything wrong and couldn't fix it if nothing was wrong. Does anyone have any Idea of what's going on?--Debbie

Reply to
Rtavi
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Drop it off Fri., ask them to start it up Mon.

Reply to
Mike Levy

problem is I work 40 miles away and have to make major imposition on others to get to work

Reply to
Rtavi

take it to another dealer. look at alldata.com for issues. It must not be electrically related as it might have logged it in the computer. Check brakes. Also have tow truck driver talk to dealership and tell them that it happened he might be able to explain it in more detail or give more information.

03-07-30-031B JAN 04 A/T - Allison 1000, Slips/Leaks Vehicle Won't Move

----TSB most closely related to your symptoms.

Reply to
Bruce Christian

The one common item between the brakes and the power steering is the power steering pump. It provides hydraulic pressure to both the power steering and the hydraulic booster for the brakes. Lack of pressure in the PS pump could cause both the steering to become almost too stiff to turn and the brakes almost too hard to press. I can't tell you why the problem changes when you start it in neutral - there is no real connection between the brakes, steering and tranny.

First, check your power steering fluid and top it off as needed. Little or no fluid or air in the lines could cause this problem. If the issue persists, have someone remove the accessory drive belt and check the pully on the PS pump. It could be loose and slipping on the shaft. If it spins on the shaft, the pump won't turn and you would have this problem. It could also be a problem internal to the pump, at which point it will need to be replaced.

If nothing appears to be wrong with the PS pump, it could be the bypass valve. This valve keeps fluid flowing from the pump discharge back to the intake even if you aren't using anything connected to it. The variable positions of this valve make the power steering easier or harder depending on how much fluid it allows to bypass. If it is stuck in a wide-open position at start-up it could cause this problem.

Good luck and let us know if you find out anything - Jonathan

Reply to
Jonathan Race

HARDLY! The problem is related to the P/S pump. Fluid from the P/S pump provides pressure for the power brakes, it's a replacement for vacuum called Hydroboost. This is why both things happen. I suspect the P/S pump is lazy in the AM after it's sat all weekend. This is a severe safety issue. Right now it only happens in the AM, in the future it could happen at any time.

To the OP, this is a warranty diagnosis/repair, they should be able to provide a loaner. Is there not a dealer closer to either where you work or where you live? The warranty repairs DO NOT have to be performed at the selling dealer, just one of the same brand unless there isn't one within 30 miles (or something like that), and then they ask that you go to the closest dealer that's equipped to handle the vehicle...

Reply to
Mike Levy

Same problem again took it to a different dealer:

Got the following printout from dealer Document ID# 1470932 Lack of steering assist When stopped or during parking lot type maneuvers-kw brake power assist oil no hard noise booster hydraulic slow low speed bind weak #PI01863-(Mar 11,2004)

Some customers may comment on lack of steering assist when stopped or during parking lot type maneuvers If vehicle passes power steering test this may be normal condition A phenomenon exists when a customer uses the brake and tries to steer the vehicle when stopped or during parking lot type maneuvers. The design of hydroboost system does not allow for steering assist under these conditions. No repairs should be attempted and any customer situations should be referred to Area Vehicle Manager

Models 03-04 Silverado Avalanche Tahoe, Suburban GMC sierra Denali Yukon Yukon xl Cadillac Escalade EXT ESV Chevrolet Express GMC savana Hummer H2

Reply to
Rtavi

I've been reading this post with interest. My '02 2500HD w/ the 8.1L has a similar issue during parking maneuvers, but I've not thought much about it. Occasionally, when I apply the brake and shift to reverse and attempt to turn the steering wheel while applying the brake, it just won't move. If I release the brake for a second and then reapply it, everything is just fine. I've never had any issues with leaving the truck sit for a few days and then not being able to steer it, etc. It does sit over the weekends often since I don't really care to suck that much fuel on joy rides!!! I leave that to the Suburban. :-( At least it gets 12 MPG.......

Kevin

Reply to
K

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