Violent Shaking From Front End

[marcolli]

Hi everyone. I've been reading a lot around here (Great source of information) for a few days and I have a problem of my own...

 

I have a 2001 Sierra z71 4wd with 56,000 miles. Recently I've been getting some shaking, not a mere vibration, from the front end between 55 and 65 mph. Whenever I go over a slight rise in the road and the front end gets a little light, the stearing wheel shakes back and forth and the entire truck sounds like it's going to shake apart. I have to slow down bellow 55, sometimes slower, to get it to stop. It's been getting worse. What do you think? Tie rod, ball joints, tires?

 

Thanks.

 

Mark

[jchitwo]

it might be a steering dampener, or a bushing on one of the A-arms that has gone bad? best thing have an alignment shop take a look, it shouldn't cost you anything, have them print you out an estimate and you might be able to fix it yourself.

[Friz]

Do you have big tires on it? Bigger tires are more sensitive to an imbalance. When you get the front end checked, have them do a balance and rotation, too.

[marcolli]

Do you have big tires on it? Bigger tires are more sensitive to an imbalance. When you get the front end checked, have them do a balance and rotation, too.

 

<{POST_SNAPBACK}>

 

 

 

No, she's bone stock.

 

Thanks for the replys. I'll make an appt tomorrow.

[71GMC_3/4T]

Sounds to me like the idler arm is shot.

Try to wiggle up and down on the steering linkage on the passenger side. If it moves much, you've probably found it.

 

They'll tell you it MUST be realigned if you change it yourself. You can believe them, or you can carefully scribe around your existing one and put the new one back in exactly where the old one was. I did this on my 83 S-10 and my 92 Z-71. Neither of them had a problem with alignment and I ran both of them for about 80K miles more after I replaced the arm.

[marcolli]

Sounds to me like the idler arm is shot.

Try to wiggle up and down on the steering linkage on the passenger side.  If it moves much, you've probably found it.

 

They'll tell you it MUST be realigned if you change it yourself.  You can believe them, or you can carefully scribe around your existing one and put the new one back in exactly where the old one was.  I did this on my 83 S-10 and my 92 Z-71.  Neither of them had a problem with alignment and I ran both of them for about 80K miles more after I replaced the arm.

 

<{POST_SNAPBACK}>

 

 

 

Thanks. I'll give that a shot. I rotated the tires this evening. It needed done anyway. Hopefully it'll help a little bit. Thanks again.

 

Mark

[marcolli]

Alright. Is the idler arm the peice that kinda looks like a phone receiver? About 6" long, round on both ends with rubber bushings. One end is attached to the steering linkage and the other to a bracket on the frame. I was able to move it up and down, but not very much at all. Just enough to be able to tell that it was moving. It seemed pretty solid.

[az'03Silverado]

If you look at the steering system take a look at the steering box on the driver's side frame rail. There's a metal arm that is attached to the box that moves back and forth to control the steering. This is the pitman arm. On the opposite frame rail (passenger's side) there's an arm there that looks similar. This is the idler arm. You're steering system has 11 points of movement (just count the zerk fittings) and any one of these or all of them can wear and go beyond specs causing vibration. The alignment folks can test them for movement beyond spec.

[marcolli]

That sounds like the part. I'll have it checked out. Thanks for all the replys and help. You guys rock.

 

Mark

[marcolli]

Well, the tech suggested new tires. He said that he really couldn't test anything else until they were replaced because they were so bad. After they replace the tires, they're going to road test it again and check the alignment. I have my fingers crossed that the new tires and alignment will fix it, but I'm not holding my breath. My luck isn't that good.

 

Thanks for all the suggestions and explanations. There's a good group of folks here. I appreciate it.

 

Mark