Hi from a not so sunny England.

I have had an intermittent clunk from the front end of my 1999 Blazer (RHD) for some time now which I have just been unable to pinpoint, it tends to happen most on sharp right turns but sometimes in a straight line too. Hub bearings have been recently replaced (Timken) & all suspension & steering joints have absolutely no play in them whatsoever. I also recently replaced the high speed CV joint on the front propeller shaft (transfer case end) as it was worn & causing vibration. Oh & before anyone asks the torsion bar mounts are OK too with no apparently play. The vehicle otherwise drives smoothly, it makes no difference if the vehicle is in 2wd or 4wd. 99% of the time it remains in 2wd Hi.

However, whilst doing an oil & filter change yesterday I did notice the inner CV joint on the left hand driveshaft (passenger side for RHD) wobbles around slightly where it goes into the differential housing. Surely this cannot be right?

What I want to know is has anyone else had experience of this, I cannot imagine that a bearing has failed in the differential or it would surely make a horrendous noise all the time. I remember many years ago having a differential carrier bearing fail in an old Ford Granada that I had & it sounded awful all the time. Why on earth would my noise be intermittent?

Are the splines liable to wear on the inner CV shaft joints & cause play? There are no oil leaks from the front differential & the oil level is correct.

Any advice would be appreciated before I start tearing stuff apart.

 

The CV joint should not wobble at all; sounds like the axle has unlocked from the differential...you may just need to push the axle back into the differential and get it to lock once again.

There is a locking clip on the end of the axle...perhaps this has broken...hope not as that would mean the pieces are in the differential and time to remove the cover.

If the axle will pull out of the differential by hand, check the locking clip condition, and then go from there.

Good luck.

 

Thank you very much for the reply. There is no in/out movement of the inner joint which would signify that the locking clip has broken, the slight movement is side to side (when viewed from the side of the differential). This to me is potentially even more worrying. Gonna have to remove the shaft & have a look, might be lucky enough to find I just need a new shaft due to spline wear, or worse the problem is inside the differential itself. I would have thought that side to side movement would make the oil seal leak but it is dry there & the oil level is where it should be.

 

Hello i have the same clunk you have mentioned. Its happens sometimes when driving and almost always when i go into drive or reverse. Im pretty sure its that CV joint causing it on mine as well but i will update you when I replace my shaft. I hope its the cv joint and not the Diff itself.

 

I am working 12hr shifts for the next 4 days so not gonna get chance to look at mine until next week sometime. I am hoping & praying that the looseness problem is just worn splines on the inner cv joint & not a problem with the differential itself. Thinking about it logically & from past experience with a failing rear axle on a Ford Granada I once owned it made a terrible whining & eventually a grinding noise as the bearings broke up. On my Blazer front differential there is no such noise, just this intermittent clunk which i'm 99% sure I've traced to this play in the inner cv joint. I will be very interested to hear the outcome of your problem blazerbagpipes. Incidentally, have you checked your CV joint on the front propeller shaft (nearest to the transfer case, they sometimes fail (mine did) and can cause the symptoms you describe. Vibration at speed is another clue of a problem here. If it is that joint then it's a fairly easy fix & a couple videos on YouTube show how it's done.

 

Hey Dave, I will keep you updated, I'm just going to get a graveyard shaft. The rubber boot is fine and the propeller shaft itself looks fine other then the mega rust and the huge wobble internally. I think the bearings are just toast. This is acually causing the front u joint to scape against my bellhousing a little bit which really makes me mad arrrg.

 

Got an unexpected day off of work today so decided to remove my front left CV axle to find out why the inner joint is wobbling around.
I have found that there is a needle roller bearing behind the oil seal that is quite badle worn & this would certainly explain why the joint wobbles around. I cannot believe the oil seal has managed to keep the oil in with that amount of play but somehow it has?
So - I have a couple questions...
Has anyone any experience of replacing this bearing &, if so can it be done with the differential in the vehicle assuming the bearing comes out from the outside of the case? Would sure save a hell of a lot of work if that were so.
Also, does anyone know the size of the bearing as it would almost certainly be cheaper getting it from a bearing shop as I wouldn't mind betting a GM dealer would charge an extortionate price for it. Obviously I will need to renew the oil seal but there is a size written on that & have already identified an SKF one online for £8 (around $13).
I don't feel happy driving the vehicle far until I have sorted this.

 

Right - another update. Having spent the last hour or so searching this forum for similar problems to mine I have concluded that I hopefully can replace this bearing with the front differential still in the vehicle.
Incidentally, I found the bearings & seals are the same for the left & right side so have ordered 2 of each, figured if the left one is that badly worn then I may as well do the right side too while i'm at it.
So - went onto the Nalley GMC website & found the right diagram with the bearings & oil seals I need but they wanted to rape me big time for shipping to the UK. So I then cross-matched the part numbers to RockAuto (who's shipping is much cheaper & have just ordered them. Just under £20 ($29-28) including shipping to the UK which i'm more than happy about.

I am just hoping that all the wobbling around hasn't damaged the inner CV joint where it rides on the bearing or i'm gonna end up ordering one of those as well. It doesn't seem to have done as far as I can see.
Will update again once the parts make their way to me across the atlantic.

 

Hey dave turns out my rear drivshaft u joOINTS Were cracked causing all the problems i had. Now (after replacment) everything is perfect i dont think i will have to touch the front driveshaft yet, but i will eventually, ill keep you posted. thanks :m )

 

Any insight on replacing the outer pass. side front axle seal and bearing?