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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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Just a few thoughts… how are the engine mounts and tranny mount ? has the truck been lifted ( there may be a drive shaft angle problem ) you mentioned checking the u-joints and center bearing. it might be possible that the drive shaft its self is unbalanced.
I think I might have mentioned this to you before but what you describe is a classic drive line issue. I would be looking at the driveshaft, U joints, center support (#1 suspect BTW) and possibly the rear differential. Vibrations above 65mph are often driveline issues in my experience and may times due to something that is out of balance within the driveline.
Take the drive shaft out and check the u-joints. replace u-joints if bad and have drive shaft balanced if not.
Look for a place on the drive shaft where a weight may have been but has fallen off or possibly a dent.
Play in the u-joint is not necessary for a vibration to exist, you could have a binding joint.
If the drive shaft is made from steel and has bad rust scale, the loss of material through rust scale can amount to ounces that can also cause balance issues.+1 on the issue been with the drive line of the truck. Eric and Jacob nailed it with what to start checking.
Keep us posted!
Thanks guys. I was leaning towards the driveline since all the suspenion stuff looks good. I was getting tired of hearing “tires, ball joints, alignment”
The truck is stock except for an exhaust, air intake, and the bilstein shocks mentioned. Just trying to get a smoother ride.
Okay, when I get some free time I will take out the driveshaft and replace the rear transmission seal (it’s starting to leak a bit). I will check out everything and I will pop the rear diff cover off to make sure there isn’t any damage – plus it’s a great time to put some nice fluid in there.
If it needs to get done a driveshaft shop that I’ve been to in the past (they do a lot of racing/custom stuff) quoted about $250 or so rebalance the driveshaft, new u-joints and a new center bearing with a polyurethane support.
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.
Maybe if I had a shop with a lift, but a dyno would be even better to properly load up the drivetrain. If the truck comes off the jack stands going 70 very bad things will happen. I would rather just pay the driveshaft shop the money to balance it and do everything right.
#1 Be Safe
#2 Stay DirtyYeah that was kind of my thoughts also. A dyno would be nice but might cost.
Quoted From Third Gear:
Maybe if I had a shop with a lift, but a dyno would be even better to properly load up the drivetrain. If the truck comes off the jack stands going 70 very bad things will happen. I would rather just pay the driveshaft shop the money to balance it and do everything right.
#1 Be Safe
#2 Stay DirtyWell, still trying to figure this out. I have the driveshaft off, the U-joints don’t seem to be too bad, but I was thinking about having it rebalanced and new U-joints, and center bearing to be safe.
I drained the rear diff and popped the cover.The rear diff fluid is pretty dirty. Lots of stuff on the magnet. From what I can see one tooth on a spider gear inside the carrier is kind of jacked up. Well, 118k miles and the fluid has never been changed. I don’t think that would cause my problem though. I’ll let you guys know what else I find.
A ‘jacked up’ spider gear is not a good sign, I hope your issue doesn’t end up to be something inside the diff that’s a lot more expensive than u joints or a center bearing. Try turning the yolk on the diff from back and forth to see if you see or feel any movement that seems excessive, I would say there should be very little play, this ‘test’ is by no means accurate but it could provide a clue to something to look into.
Well, it’s not the driveshaft. Rebalance, new u-joints and new center bearing. Low speed seems to be a bit smoother. But I still get the shaking on the highway. I get a feeling it’s something in the front end.
I hope not either Eric, I don’t remember there being too much play, but then again differentials aren’t my thing. It does move when you twist it, maybe like 10mm or less. Maybe I can find something in the service manual. I but I just think that is wear and tear on the ring and pinon.
Now I have a new problem as well, when I take off fast or come to a stop quickly I can feel a clunk. So I’m not sure what the heck is sliding around. This truck will be the end of me, lol.
Well the clunk that I feel, I’m not sure, it might have always been there and since the driveline is stiffened up a lot it is noticeable now. I have a new transmission mount too. I’m sure I’ll figure it out.
In regards to the shaking/vibration I might be onto something. I was rechecking my front suspension and I’m getting a noticeable clicking from my driverside lower ball joint when I use my giant pry bar on it. I used my stethoscope and it is the loudest when it’s near the ball joint. So I’m 99% sure that is an issue. Not looking forward to doing the job, but it will get done.
Second. I think I may have a wheel bearing going out on the passenger side. With the wheels in the air, there is noticeably more drag on the passenger side wheel. If I spin the wheel as hard as I can, I can only get 5-6 revolutions. The driverside I will about 11 revolutions sometimes 12. I loosed up the guide pins on the caliper a bit and that had no effect. Plus, when i put stethoscope to backside of the bearing/hub assemblies the passenger side is probably twice as loud as the driverside.
So I think that maybe my shaking is combination of ball joints and wheel bearings that are on their way out.
Thoughts?
Bearings usually make a loud howling noise when they are on there way out. You could raise the vehicle and grab the wheel where the possible bad bearing is, place your hands on at the 9 and 3 o’clock position and check for play.
For the clunking sound, is it always present no matter how long you have been driving your truck?
I remember I could get a little bit of of a click from the passenger side when I held the tire at 12 and 6 o’clock position. I know traditionally the bearings howl, but I have a habit of receiving unusual symptoms. I thought the huge difference in how many rotations I can get out of the driverside versus the passenger side might be an indication that passenger side is on its way out.
As for the clunk, it really isn’t audible – you feel it inside the truck. This is new to me. It started after I put the driveshaft back in and new transmission mount. After driving it a little more, it seems like you will only feel it when you come to a dead stop and the weight transfers to the front. Conversely, you will also feel a clunk when you take off from a dead stop and the weight transfers to the rear. The only thing that pops up in my head is possibly a motor mount.
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