# 2000 NBS Vibration



## mayhem (Aug 25, 2006)

2000 Silverado 3/4 ton 4x4. Feeling a vibration that seems like its coming from the front. Its speed dependant. I have also recently started hearing a clicking/pinging noise from the front if I'm moving at slow speed in the driveway, almost sounds like a the sound a metal flagpole makes when the wind plows the flag and the metal grommets ping against the hollow pole. The noise gets louder in 4wd, but I cannot feel anything through the steering wheel or pedals.

I'm thinking u-joints in the front driveshaft or maybe a bent shaft, but wondering if anyne has another suggestion. Obviously this is better to find and fix now and not ignore hopeing it'll go away.

Over the winter I had both front wheel bearings replaced as well as the driver's side CV axle assembly (due to a torn boot when I tightened the last bolt on the bearing). I'm skeptical that the noise is from the front end or the garage would have caught it and soaked me to replace it.

Truck rides rough due to the vibration but does not seem to have any loss of stability or directional control.


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## B&B (Nov 4, 2006)

Remove the front D-shaft and go for a test drive. If the noise/vibration is gone then you know you're on the right track for needing U-joints.


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## mayhem (Aug 25, 2006)

I was wondering if that was safe to do...figured it was, but you never know. Just pop the nuts off the yoke and pull the shaft out, right? Safe to assume I don't want to leave it out for an extended period?

Is there a test for bad u-joints or obvious sign of physical wear? Slop in the driveshaft or clunking noise or something?

Thanks.


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## B&B (Nov 4, 2006)

You can run indefinitely without the D-shaft, or until you get stuck and really wish is was on there now. 

Yes just a few bolts and cut the metal band from the boot at the T-case end and work it off. Simply working the joints by hand once you have the shaft removed will probably reveal they feel too tight (dry), notchy or rough. But if it's a high mileage unit and you have the shaft removed anyway it's a time saver to just replace them regardless at that time.


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## mayhem (Aug 25, 2006)

Yeah, turned 140k last Thursday. Bought it with 90k and I've never replaced them. Don't know if they were ever replaced, so its probably certainly due regardless.

Thanks again.


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## mayhem (Aug 25, 2006)

Got under there last night, the joint coming out of the transfer case has about 1/8 of a full rotation worth of slop in it and when I rotated the shaft I could hear the noise thats been bugging me.

So its off to NAPA I go today...might as well get the rear shaft joints too and do them all. Any tricks I need to know? Never changed U-Joints before but it looks fairly straightforward. Do I need to grab any gear oil too to top off the t-case or front differential when I pull the shafts out of there?


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## mayhem (Aug 25, 2006)

Unclear on the removal bit. I see the 4 bolts that hold it on the front yoke, the part that goes in the t-case though appears to be one piece. If memory serves there is a button release on the shaft that will allow me to putt it out ot the t-case like the PTO shaft on the back of a tractor...but if I do that I leave a hole in my transfer case allowing dirt in and tranny fluid out, right? Is this where I'll see the metal band you refer to? Like to remove the driveshaft so I cna bench the thing and work on it at my leisure instead of trying to rush it.


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## B&B (Nov 4, 2006)

There's nothing holding the shaft in the T-case except the boot and it's band clamp. Once you cut the band loose the shaft can be removed from the T-case. It's just a male/female splined deal. No fluid will be lost either. 

Now with that being said, sometimes the splines do get a little tight so it takes a little tapping to get them apart but there's nothing technical about it, just a little gentle persuasion sometimes.


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## I HATE RUST (Oct 9, 2010)

mayhem;1283493 said:


> 2000 Silverado 3/4 ton 4x4. Feeling a vibration that seems like its coming from the front. Its speed dependant. I have also recently started hearing a clicking/pinging noise from the front if I'm moving at slow speed in the driveway, almost sounds like a the sound a metal flagpole makes when the wind plows the flag and the metal grommets ping against the hollow pole. The noise gets louder in 4wd, but I cannot feel anything through the steering wheel or pedals.
> 
> I'm thinking u-joints in the front driveshaft or maybe a bent shaft, but wondering if anyne has another suggestion. Obviously this is better to find and fix now and not ignore hopeing it'll go away.
> 
> ...


My 03 with 110,000 miles just started making a sound just like that when I come to a stop when the motor is still cold and in the first 10 seconds after I start it up. I am not feeling any vibrations that I can tell. The interesting thing is at my work we have a brand new GMC dump truck that makes this same noise so idk.


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## mayhem (Aug 25, 2006)

Got the front shaft out last night around midnight. Took a good 45 minutes to get it unfastened, most of that time was spent getting the band off the bot by the t-case, another 15 minutes of wiggling and a few harsh words at it and the thing finally came out of the t-case. Truck rides alot more smoothly now, I'm betting the rear u-joints are in need of replacement as well. 

Now I've got the driveshaft on the bench and I've got the new u-joints...I'm guessing the swapout if relatively straightforward and the real challenge will be to get the thing back into the truck. Any tips for swapping the u-joints themselves? I opted to soak the things in WD-40 to help loosten any rusted clips or clamps and will have a look some evening this week at it. 

Also, what do I replace that steel band with on the boot? Just a hose clamp ok to use or do I need to locate a Chevy dealer and order a clamp?


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## B&B (Nov 4, 2006)

se a plastic wire to to refasten the boot. Hose clamps have too may sharp edges and tear the boot up rather quickly. Not to mention on an Autotrack equipped truck such as yours maintaining the balance of the D-shaft is important and the offset weight of a metal hose clamp is enough to create a new vibration, which goes against the whole point to the repair in the first place.

If you new to changing U-joints I'd recommend having someone with a little experience with them assist you on you first ones to save yourself some grief and possibly some prematurely damaged parts too. U-joints aren't complicated but done incorrectly will cause you more problems than you're trying to solve. If you can't find an experienced helper at least dig around on the net, I'm sure there some good step by step writeup's on them.... probably even some videos if you look enough. If you find one that recommends whacking on the yokes with a hammer move on to another writeup because contrary to popular practice that isn't the proper way to do it.


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## mayhem (Aug 25, 2006)

The first 5 how to replacement articles I've read all say to tap the old joint out of the yoke with a hammer and a socket or other stiff implement to apply the striking force on the old joint, not the yoke. 

Is this the wrong advice you were referring to?

The process looks fairly simple except that I didn't mark the alignment of the shaft to the front differential...not sure how significant of an issue that is. I assume that after I get it reassembled if I notice significant vibrations that I can just rotate the alignment 180 degrees.

I accidentally tapped the 4wd button while moving yesterday...should have been a non issue I should think as I was only moving about 30mph. The transfer case made a sound like a garbage disposal. I stopped, shifted back to 2wd and no noise...shifted back to 4wd while stopped and no noise even up at 50mph, but then when I shifted back to 4wd at about 20 mph ot made that same noise again. Thoughts? Something to do with the lack of a driveshaft in there or is this a secondary issue I should address while I'm half disassembled and its nowhere near winter?


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## mayhem (Aug 25, 2006)

Apart from the hammer "taps" to loosten the cups, does this look about right?


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## B&B (Nov 4, 2006)

Without a press you will of course have to pound or press (with a vise) the joint caps out and then back in during assembly, just don't pound on the D-shaft yoke itself. Guys often do that in order to break the U-joint caps free and it very easily distorts the ears of the yoke in the process causing new problems. The video is ok but he overlooked or didn't show cleaning the rust/corrosion out of the yoke holes before installing the new joint. So be sure to do so with a little sandpaper.


There's likely nothing wrong with the T-case. You simply can't (and shouldn't have) engaged 4WD at speed with the D-shaft removed on an Autotrack equipped truck. Without it there's nothing to bring the 4WD components up to road speed before it attempts to engage, thus you get the blender sound. So be sure to stay way from the buttons until you get it re-installed and all should be good.

This is also a good time to check the fluid levels in both the front diff and T-case if it's been a while since it was last done. They're two of the most often overlooked components during routine services so while you're under there installing the D-shaft would be a good time to check their fluid levels.


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## mayhem (Aug 25, 2006)

Got it, thanks again B&B! A real life saver.

Should I just top off the fluids as necessary or are there convenient drain plugs and I should just do a full fluid change? Likely never been done...at least not in the last 50k miles. Do you have a recommended fluid you like to use?


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## B&B (Nov 4, 2006)

If you don't know when they were last serviced then doing a proper drain and refill would be a good idea if you're looking to maximize their life. They're both easy to service just be sure to use the correct fluids. For the front diff any brand name dino based 80W-90 is fine or if you'd like to upgrade to synthetic a 75W-90 fluid would also be a good choice. The T-case is a little different in that it needs it's specialized Autotrack ll fluid that is only available from the dealer so it's not quite as convenient but is necessary to do it correctly. 

Both the diff and T-case have drain and fill plugs so there's nothing difficult to servicing either.


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## mayhem (Aug 25, 2006)

Fantastic! Thanks again.


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## mayhem (Aug 25, 2006)

OK, I've been beating ym head against the wall for awhile and maybe I need some fresh perspective. How the heck am I supposed to get the little snap rings off the old u-joints? I can't get a scredriver in there, nor any other tool at my disposal. I pulled one of the free caps off and verified that they have the C-shaped snap rings that go on the inside of the yoke, not on the outside of the roller bearing covers...but I just can't get a grip on them. I've been soaking the old joints in PB Blaster daily for a few days but I feel like I'm missing something obvious. I googled and youtubed for answers on how to get them off, but all the procedres I've found all just say "remove the snap rings" as though its the easiest part of the whole operation, so I've got to be missing something.


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## 06Sierra (Nov 30, 2008)

Have you tried snap ring pliers?


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## mayhem (Aug 25, 2006)

Before I started this process I had never heard of them. All the DIY writeups seem to say to use snap ring pliers if your joints have the external spring loaded snap ring that goes on the outside of the roller bearing cup, but for the C- shaped rings they all say to just pop it with a screwdriver and a hammer, the mimplication is that there isn't a specialized tool for these kinds of rings, but I don't actually know that.

Is there a snap ring pliers for the kind of rings I'm pulling out?


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## B&B (Nov 4, 2006)

There is no special tool or procedure to remove the C-clips so that's why you didn't find much info while looking around. They're not conventional snap rings so there's no eyes to grab with snap ring pliers, you use the hammer and screwdriver method. Look at each end of the clip you want to start with. One of the ends will have a slightly larger gap between it and the yoke to allow a little more working room with the screwdriver and that's the end you want to start with. Place the screwdriver on the END of the clip and whack it hard with the hammer. Sometimes the gap is just right that it will even allow you to use the yoke to pry against the end of the clip with the screwdriver. 

If it's very rusty (they usually are) it will take some force to begin to move but it will eventually. You may even break a section of the clip out (be sure to have eye protection on) which is great because then it's even easier to get the screwdriver on the end of the remains of the clip. Then you just continue hammering at it until all the clip is removed.


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## 2COR517 (Oct 23, 2008)

A ball joint press will work well to change the u-joints. You can get them at AutoZone through the Loan-A-Tool program, and other stores or tool rentals.

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## mayhem (Aug 25, 2006)

OK, this is driving me nuts here. What am I missing?

The photos below show the axle end of the u-joint, there do not appear to be any c-clips on these suckers...if there are, they're not c-shaped, but are complete rings. The second photo shows one of the caps that came off the other parts of the same joint, it clearly has a c-clip on it. The joint caps that are inside the yoke and on the other end do not appear to have c-clips.

I've read something about that the OEM GM u-joints have some plastic clips that need to be melted off before the joints cna be removed. Is it possible that at 141,000 miles (I bought the truck with 91k) that these are the original u-joints and I need to melt something?

I've soaked this in penetrating oil, scraed at it, smacked the caps with a hammer on a 3/8 to 1/2 inch socket changer and I don't seem to be getting anywhere. I know I'm doing something wrong but I don't know what it is.

Thoughts? Othar than that I'm an idiot or that its a good thing I don't need 4wd right about now?


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## B&B (Nov 4, 2006)

You have one of the ones that used the hot injected plastic to retain the caps instead of clips. Heat each of the yoke ears one at a time with a handheld propane torch until the plastic begins to "snake" out of the holes in the yoke where it was originally injected in. Continue heating until no more plastic comes out and then just press the U-joint caps out like normal.

It's obvious this is this guys first time with one but it'll give you the idea. 




Be sure to wear safety glasses while doing this procedure as the plastic and/or remaining grease can "pop" spraying out hot grease or plastic. Don't need that in your eyes.


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