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1999 GMC Sierra 5.3 Extended Cab RWD. A long time ago I talked with Eric about this. Okay, I’ve been dealing with this problem ever since I got the truck in 2010 mostly because money is tight and I don’t want to throw parts at it. The main problem is on some freeway surfaces, I get an intense vibration/shaking between 60 and 70 miles per hour. It will usually stop after 70, but it can still be felt slightly. The shaking can be felt through the entire vehicle and the steering wheel. It feels like someone is grabbing you and shaking you 4 or 5 times per second. I haven’t gone through everything in the service manual, but I will tell you what’s been done.
I’m on my 2nd set of tires. Original tires did this – had them rebalanced several times. I bought a new set of BFGs – basically the same thing – balanced several times. I got the tire shop to replace the BFGs with Michelins (The most expensive tire for this truck) – same thing. Balancing doesn’t effect it very much.
I’ve taken the truck up to 75 MPH and then put the truck into neutral. Coasting down through the problem range – problem is still present.
The shocks are Bilstein heavy duty – perhaps a little too stiff, but all the shocks did was make the shaking/vibrating more noticeable. Ride can be a little rough though.
I’ve had two alignments within the past year. A GM mechanic I spoke with blames the alignment – this doesn’t make sense to me.
I’ve retorqued the ball joint nuts, lower control arm bolts, power steering rack bolts, tie rod ends, sway bar end links.
Ball joints do not appear to have any play when a giant pry bar is placed underneath the supported tire.
Truck has a two piece drive shaft. There doesn’t seem to be any play in the center bearing or the u-joints.
Some things I’ve also noticed: if I have an extra four or five hundred pounds in the truck (cab or bed) the vibration is greatly reduced or is eliminated. I do not think I am suffering from the infamous “frame beaming.” This shaking is much too intense.
I haven’t had a change to get under the truck to measure the suspension per the service manual but I found this interesting.Measuring from the top of the tires diagonally to the fender I get different measurements (my 1990 regular cab is basically the same side to side).
Front left: 5 and 1/16 inches
Front right: 4 and 3/4 inches
Rear left: 6 and 1/4
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Well, it’s a real pain in the rear, but I got one lower control arm off (and luckily haven’t killed myself with any coil springs) and it the lower ball joint is completely toast. Like if it’s horizontal, I push it up and flops back down…. I’m glad I finally found SOMETHING broken. I’ll keep you guys updated.
I was going to do the bushings on the lower control arm too just for the heck of it, but the ones they sent me look like the 4WD ones and I have RWD…. they still look okay, so I will just send them back. Looking around online I think only the dealer sells the RWD lower bushings. Oh, well.
I’m glad you found something wrong I hope it fixes it. If not, I know you said you changed tires and had them balanced but have you looked at your rims? I’ve had an issue like this before and it ended up being a slight bend in the rim that wasn’t that noticeable.
Well, I will tell you guys if I ever get it back together. The rivets that hold in the OEM ball joint are a real pain. Get the heads off, no luck. Heat ’em up, no luck. Air hammer, no luck. Drill ’em out, no luck. I gotta keep at it though, I kinda need this thing working for tomorrow. I’m kinda mad at GM for this one. I should be done with the whole project by now.
I usually just cut the heads off of the rivets with a cutting wheel and I’m done. I wouldn’t have much hope for that fixing your problem however as loose suspension parts can make a vibration worse but not be the cause of the problem, rotating assemblies cause vibrations at speed, nothing else really.
Well, I’m sure worn out ball joints don’t help the situation at all. Oh, I was able to get the rivets out. I don’t know why but I had to cut off a head, and then drill it out about halfway then I was able to pound it out with my mini sledge and an old bolt. GM wasn’t kidding when they say “center punch rivet, drill out rivet.” I bought a new set of cobalt bits, and it really sped up the process ten fold. My old set wasn’t liking that hard metal at all (yes I use cutting oil). I will let you guys know how it does on the road.
Ball joints were toast. So now I have new lower ball joints, new GM upper control arms, and I also did wheel bearings/hub assemblies. The wheel bearings were running dry and starting to make noise so I thought it was a good idea to replace them. The ones on there seemed to be some no-name China brand, I put on SKF assemblies which looked extremely well made and had excellent machining on them. While I was in there I did some Energy Suspension end links and sway bar bushings.
Now the truck drives like brand new on the street, but I still get a vibration on the highway depending on the surface I’m driving on. I’m not giving up on this yet. My next thing to consider is maybe resurfacing or replacing the rotors – maybe they have too much run out or something else.
another thing I was thinking about is to find a good frame shop to have them see if something got tweaked somewhere down the line so that’s why I’m having this weird issue. Autocheck for this vehicle did indicate a “minor” accident on the passenger side, so it wouldn’t hurt.
Loose suspension parts will not cause a vibration, they can make it worse but they are not the cause, rotating assemblies cause vibrations, that’s why they are speed or RPM specific, if it was a suspension part it would happen all the time, it’s either in the drive line or the tires. I don’t believe your going to get any results from machining or replacing the rotors unfortunatly.
I’m not saying replacing the worn parts you replaced wasn’t a good idea but there was no hope of that solving the vibration issue.
I understand Eric, but I am running out of things to look at.
So, really the only things left to rule out are the rear axle and the engine/transmission – which I don’t think I have the ability to diagnose at my house.
I know you’re a broken record about tires, but what else should I try in regards to the tires? They’ve been rebalanced a good half dozen times and it’s done it with other tires. The rims don’t have any damage on inner or outer lips. Unless I try another shop or somehow try another set of rims and/or tires I’m stuck with those rims and tires.
It might be worth it to try and find a friend of friend where we can swap tires and go for a drive.
Quoted From pcmdjason:
I’m not sure if there’s a safe way to do this, but if you could some how elevate the rear tires and spin them up to 70-75 and put a strobe on the drive shaft which you had marked with a white crayon every 36 degrees or so and adjust the strobe so you could see if you could see the drive shaft wobbling.
be sure you put the real good universal joint cause one time the part guy make a mistake when checking in the computer for unversal joint cause you have steel drive shaft and aluminium drive shaft and th unviversal joint look the same!! mine was steel drive shaft and i had put one for aluminnium drive shaft lookkk pretty the same and fit correct on a chev colorado and had cause vibrations at this speed i had replace for the steeldrive shaft the problem was solved
I didn’t install the u joints.I had the driveshaft shop do it since I had them rebalance it. The only thing they do are driveshafts, so I’m sure they got it right.
Is the truck running at the stock suspension height? Im curious if the operating angles of the U-Joints are not within spec, most vehicles being between 3 and 5 degrees.
Yes sir, no lifts or lowering kits. Although, I do have Bilstein HD shocks front and back(they have light and HD). One thought I had is maybe the rears are too stiff for when I’m not carrying weight in the bed. I’m pretty sure I didn’t keep the old shocks – which usually I’m pretty good about saving parts until I’m 100% sure I don’t need it.
I want to try and find someone who will swap wheels with me to rule out the tires/rims – I want to keep the oem rims since the tires are brand new. But I suppose some Silverado SS rims would look nice though.
Another thought I had was putting it on a dyno have them drive between 60 and 70 to see if anything is noticeable in the rear or drivetrain.
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