Mystery Slack/Play - Wheel hub? CV? Ball Joints? (2008 Yukon Denali)

I've got a mystery issue involving play in the front end. If the vehicle is on the ground and you grab the top of the front wheels (on both sides) and pull, you feel play and get and feel a 'clunk' like you would with a bad wheel hub and possibly a ball joint. Jack up the front end by the frame and then the lower control arm and you have no play/clunk. The ball joints, CVs, wheel hubs, U joints, transmission check out. The 'play/clunk' is detectable on both sides.

Now here's the kicker. When you put the car in gear you get a loud 'click', not a clunk, but a click randomly. On the ground with the ball joints and bearings in the hub loaded there is play if grab the wheel at 12 o'clock and give it a stiff pull. Lifted for the various tests, no play of clunk. The tie rod ends are good that the steering rack is good. I had the vehicle aligned about 3k miles ago and took it back to the shop that did the alignment and they said they can find on wear that would account for this issue nor could they explain it upon examining the vehicle. I took it to a seconds shop at the first shop's recommendation and they couldn't figure it out. We even threw runout gauges on the hubs and nothing. But the play is there and it clicks loudly when you put it in gear in reverse or forward (had the transmission checked to preclude that and nothing). Yest the play is still there.

That said, there is no unusual wear on the front tires or back tires, no drift when you go down the road or brake, nothing unusual. Both wheel hubs are new (one had about 15k miles and the other about 7K miles) and everything is torqued properly. I'm leaning to concluding both hubs spontaneously failing in a bizarre way, but I'd rather not have to unnecessarily go through changing them.

The only other thing that I did was to replace a welded in bracket for the front stabilizer bar, but the weld is good and nothing out of order in that department. This started after I had the bracket replaced but that wouldn't explain the symptoms. Any thoughts? What am I missing here? I mean, other than my marbles.

so with the truck on the ground, you grab the top of the tire, pull or push and it clunks? but no when you jack the truck up from the bottom of the a arm as close to wheel as you can get it doesn't?


can you have a 2nd person do it while you're under it looking. odd it was on a drive on alignment rack where someone should be able to watch closely while it clunks and can't seen anything moving funny.


only other thing I can think of is get a long bar or pipe under the tire while it's off the ground and pull up. see if you can get some clunk from it then. you're going to have to see or feel every joint for the slop. especially the upper a armed to frame thru bolts.


as for the click, I've had to cars click when you hit the gas from a stop after braking, both were center axle nuts that needed torqued to spec. the fwd I know no one worked on it. it just wasn't tq right at the factory or something. the other rwd, I had 80k on it and a unknown history. someone might have been in there and not tq it back. both have never clicked again.

@Gildan I would try the same test and try grabbing it at the 6oclock this time, I wonder if the tires touching the ground causes the lower balljoints to be more pronounced VS when you have the control arms on jack stands.

But it also sounds like you have more than one problem happening at the same time so don't assume they are related, the steering knuckles are so far away from what's happening when you shift between between D and R.

Yeah, did all that. But I didn't think of re-torquing the spindle nut! I never thought of that. The 'play' might me the splined shaft knocking in and out and I can see that happening on both sides (and even on one side being felt on the other side). Never thought of that.

That's fascinating because there is a slight amount of play that you can feel on these hubs under the right conditions when the bearing is loaded, so to speak (which is not a normal way to check play in bearings like this). As a point of physics, there has to be a certain minimum of "slop" in any mechanical system or it will simply lock up and do nothing. This may save me a lot of PITA (Pain in the arse) time and money if that's the issue which, upon further thought, may be the problem.

Replacing wheel hubs is easy, but expensive. Replacing ball joints is inexpensive up a pain in the *ss. I had this happen with a Honda back in the 80's. Hit a pot hole and the bearing was loose. I implored the mechanic to just torque the spindle nut to the proper specs and that fixed the issue. However, he was disappointed because he couldn't sell me a new hub and CV joint. LOL!

I'll give a re-torquing of the spindle nuts a try and see what happens.

A long shot...... Your front differential bushing/mounts may be starting to fail. Mine failed rather badly, so it was a clunk, rather than a click. But, you may want to check them anyway.