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View Full Version : OT: Auto Steering Problem



Paul Alciatore
05-11-2009, 02:16 AM
I know there are a lot of auto types here. I have a 2000 GMG Sierra and the steering is hard to turn to the right when first started up in cold weather: not left, just right. It has been getting worse for about 1-2 years now and even though the weather is warmer now, it still does it somewhat. They say they have replaced all the cheep stuff and all that is left to try is the steering gear itself.

I am just wondering if there is some known problem with this model that may have been overlooked. Preferably one that is not expensive to fix. Any ideas?

Evan
05-11-2009, 06:49 AM
Tire rubbing on something?

Slipping steering pump drive belt?

Bent tie rod?

Something to try in a large parking lot with no traffic or parked cars: Take it up to about 10 mph and then put it in neutral and turn off the engine. Then make left and right turns and see if you can detect a difference with no power or pump running. If so then it's in the steering gear somewhere.

JCHannum
05-11-2009, 07:10 AM
Is it rack&pinion steering? If so, replacement is probably the only cure.

Doc Nickel
05-11-2009, 07:12 AM
That's an odd one. Only two things I could think of- that would create drag in only one direction- is either there is some issue with the fluid bypass valve in the steering box, or your steering damper (looks like a shock absorber) has a bad check.

And the check for that is to raise the front end so the tires are off the ground, and try to turn the steering wheel with the engine off.

If it's still harder to turn one way than the other, look at the damper. If it's equally easy to turn either way, it's the steering box check. (Or valve, whatever you want to call it.)

Doc.

Doc Nickel
05-11-2009, 07:18 AM
Is it rack&pinion steering? If so, replacement is probably the only cure.

-They still use a recirculating-ball steering box.

Doc.

Evan
05-11-2009, 09:43 AM
Low pump pressure from a slipping belt can do it. The steering geometry with power steering isn't always the same in both directions but with full assist it isn't noticable. It will also cause a problem if it is variable rate steering.

saltmine
05-11-2009, 03:18 PM
We used to call it "morning sickness" when I was a Chevy mechanic....

It's caused by the teflon seals in the "spool valve" of the steering box. These seals get worn, and on a cool morning, don't pop out and seal against the cavity of the "spool valve" housing. BTW, the "spool valve" is a hydrualic metering valve designed to deliver power boost to the steering based on the direction and force of the steering input. When the seals "blow over", no boost is delivered to the power section of the steering box.

The "cure"? Well, one or more of the commercially available "snake oils" are worth a try. In the shop I had some success with completely flushing the power steering system with new fluid. Failing that, the steering box can be disassembled and the seals (teflon rings) can be replaced. (UH, don't try this at home, unless you're experienced at things like this)
Last resort would be a remanufactured steering box replacement.

Fasttrack
05-11-2009, 03:25 PM
We used to call it "morning sickness" when I was a Chevy mechanic....

It's caused by the teflon seals in the "spool valve" of the steering box. These seals get worn, and on a cool morning, don't pop out and seal against the cavity of the "spool valve" housing. BTW, the "spool valve" is a hydrualic metering valve designed to deliver power boost to the steering based on the direction and force of the steering input. When the seals "blow over", no boost is delivered to the power section of the steering box.

The "cure"? Well, one or more of the commercially available "snake oils" are worth a try. In the shop I had some success with completely flushing the power steering system with new fluid. Failing that, the steering box can be disassembled and the seals (teflon rings) can be replaced. (UH, don't try this at home, unless you're experienced at things like this)
Last resort would be a remanufactured steering box replacement.

Ditto what saltmine said. We had several of those come into high school shop and the usual repair was snake oil. Highschool students are too broke to buy new components, usually. We replaced one box and rebuilt the one that came out of the vehicle as an excercise - and it was an excercise. My '89 chevy is pretty bad about this, too.

Doc Nickel
05-11-2009, 03:30 PM
Low pump pressure from a slipping belt can do it. The steering geometry with power steering isn't always the same in both directions but with full assist it isn't noticable. It will also cause a problem if it is variable rate steering.

-GM's large-truck steering is neither variable-rate (unless you include the concept of Ackermann) nor variable geometry. It's pretty standard pitman-arm/drag-link/tie-rod stuff.

And it's almost impossible for a serpentine belt system to slip enough to reduce pump output significantly, without severe and noticble damage (heavy squealing, broken idler, etc.)

Doc.

Paul Alciatore
05-12-2009, 03:21 AM
My shop already tried flushing and new fluid. I well look at the local parts stores for "snake oil". If that does not do it I guess I will just bite the bullet.

Thanks all.

saltmine
05-12-2009, 07:12 PM
It's a shame you couldn't find a real "old fashioned" automobile mechanic, Paul. When I was working, we rebuilt or overhauled almost everything. Seldom did we opt for a rebuilt, remanufactured, or new part unless the original was so badly damaged it couldn't be repaired.

But, sadly, corporate greed and managers' quest to "make money, and lots of it", have driven off all of the real Mechanics, which were then replaced with poorly trained, glorified parts changers. It's a sad state of affairs. I worry who's going to fix my car when I no longer can.

Paul Alciatore
05-12-2009, 10:31 PM
It's a shame you couldn't find a real "old fashioned" automobile mechanic, Paul. When I was working, we rebuilt or overhauled almost everything. Seldom did we opt for a rebuilt, remanufactured, or new part unless the original was so badly damaged it couldn't be repaired.

But, sadly, corporate greed and managers' quest to "make money, and lots of it", have driven off all of the real Mechanics, which were then replaced with poorly trained, glorified parts changers. It's a sad state of affairs. I worry who's going to fix my car when I no longer can.

Well, in a sense, I couldn't agree more. I am a TV engineer and have repaired many electronic, electric, mechanical, pneumatic, etc. items down to the component part level. In some cases, I actually made the replacement parts or refurbished the existing ones. I have also rebuilt carburetors, brakes, starters, alternators, done bodywork, etc. However, today many repairs are done via circuit board or assembly level replacement. This is often more cost effective. I could repair the boards, but it would take more of my time than they cost. So I only do it if good boards are not available.

Unfortunately at the present time I do not have the time to undertake my own auto repairs so I am going to the best shop in the city. I really can not argue too much with their approach as they could put several hours into rebuilding the steering gear and another hour or two to take it off and put it back on and then something could still be wrong and they would have to make it right. By using a rebuilt part, they eliminate much of the risk as the rebuild shop will replace it if it is bad so they only loose the in/out time. And I doubt that the local mechanics are good enough to rebuild such assemblies. That's the shame. What I do look for in a mechanic is one who can at least pinpoint the problem to the correct assembly.

Actually, in a sense the part is being rebuilt, just not locally and I do not get the same part back. It is probably just as cheap this way and less risk for both the shop and myself.

In the Army, in Vietnam I was with a maintenance battalion. We replaced engines, transmissions, transfer cases, etc. The bad assemblies were not thrown away. They were shipped back to a depot to be rebuilt. Vehicles got back to the troops a lot faster and the actual repairs were done by experts.

So, I agree, but I also see their point of view. The world is what the world is.

gmatov
05-13-2009, 01:04 AM
Paul,

A fellow I knew who was a rep for a rebuilder told me that HALF their rebuilds would be defective. 50% return rate.

If you buy a piece of crap, that is one thing. You lose time when you have to take it back to have it replaced.

You are paying a mech to replace something, it does not work, the mech is NOT going to charge you ONE X the labor for replacing multiple instances of that component. THEY buy the part and it is no good, I, how can I stress that, EYE think they should eat the labor.I think I got ****ed over in this way a couple weeks ago.

I,EYE, bought the motor for my kid's car. THEY put it in, it was locked up, get the motor replaced, they pull the bad one, put in the good one, I pay more.

I should have told them to buy the motor. THEY bought a piece of ****, THEY have to pull and replace, though they MIGHT **** me over a little. I COULD argue a bit about that, I think.

Saltmine,

It is hard to find anything ON a car today that CAN be rebuilt. Calipers, OK. CV joints, if you know how, OK.

Got a 90 Audi back from the mechs, today. Gave that to the daughter some months ago because they needed another car. Didn't, in the short run, but mine own Audi broke, months in the garage, had to drive that one. Got mine fixed, gave that one to the kid, 2 weeks later, he dumped the tranny.

I am not a prick. He is my grandkid. Just HE happened to be driving it when that sumbitch broke.

Worse is they tell me to let the kid take the friggin' car and DON'T have my bill made up.

Cheers,

George

saltmine
05-13-2009, 09:50 AM
Yep, BT, DT, George. A good tech should have checked the motor before he installed it...saves a lot of grief later on. Must have been a used unit, right?
I never had problems like that, since we didn't do too many used parts.

But, when I did, I always tried my best to get the motor going and make sure it was sound, before I went to the trouble of installing it.

It might have been your approach, too. If a customer rolled up out front with a wrecking yard engine and told the boss "I want this installed in that car." That's what you'd get. Way too many guys in the business are so focused on the "bottom line" they overlook the craftsman angle of the job. Today, it's gotten even worse, pay is much lower (to the tech, that is) and the skill level of the average tech has fallen off by a tremendous amount.
"Time is money" and it's a lot cheaper to throw a rebuilt or remanufactured part in, than it is to actually try to fix something any more.

Audi makes a good car...but I wouldn't let a kid drive one. My daughter had one years ago. She drove it probably one week a month....it spent the other three weeks in the shop, waiting for parts, or for her to come up with the cash to fix it. I told her to get rid of it, and just get a mainstream, generic, American car. Well, being like her 'ol man, she went out and found a 1991 Dodge Spirit....that "needed work". (from one extreme to the other)
BTW, she lives in Missouri, and I live in Arizona. Anyway, after dumping four times the value of the car into it, and having to deal with a bunch of inbred, hayseed, mechanics, she finally called me and asked for help. I told her to get rid of the Dodge...If nobody wants to buy it, push it into a nearby lake, but get rid of it!

With my help, she found a gently used '98 Chevy Lumina. Suddenly, all of her car problems ended. She's been driving the car now for five years, got it paid off, and aside from normal service, has never had a problem with it.