Odd Suspension Knock

About a month ago, I replaced the clutch on the 2013 Mazda 5.  Getting the axles out required a LOT of torching and banging and drilling and prying on things.  I suspect I managed to break something in that process, but I'm not sure what.  When I drive over the most uneven surfaces I can find, everything is quiet.  I've put the car up on the lift and used the tranny jack to load both corners, one at a time, and there's nothing that appears to bind or make any noise.  I've checked the brakes and the lugs and everything is tight.  It didn't do this before I started beating on it so it's something I did for sure.  The right ball joint got destroyed in the removal process, so a new one was pressed in.  Other than that, there are no new suspension components.  I don't have any movement on the wheel when I try to rock it side to side or top to bottom.

What I do have, however, is a knock as I come to a stop and then a second knock when I pull away from that stop.  Sometimes it's a couple knocks in rapid succession, but it doesn't keep doing it.  It's almost like the weight transfer pops something out of place and then it gets popped back.  I can feel it in the footpan and it sounds like it's coming from the right side, but you know how cars can telegraph sounds around.  If I come to a stop with the handbrake or if I'm reaaaaaaally light on the regular brake, no noise.  That's what made me go look at the brakes, thinking that maybe I left a caliper bracket bolt loose or something.  If I'm rolling forward and use reverse plus the clutch to come to a stop aggressively enough, it'll pop.  Happens on smooth pavement as well as over bumps - but only when braking.

I'm suspicious of the ball joint since it's a parts store generic type if memory serves, plus I've never had great luck with replacing press-fit ball joints.  I'm thinking about getting a new Moog control-arm-plus-ball-joint assembly to see if that fixes it.  I hate just shotgunning parts, though.  Other than the shake-the-wheel-back-and-forth-test (which it appears to be passing), what other test could I do to try to find exactly what is making noises?

Motor and transmission mounts can cause weird stuff like this to  happen.  

Second a motor or trans mount 

I was also thinking a motor or trans mount from the description, it makes perfect sense. The banging and prying probably did one in.

In addition to the motor mount suggestions, as those are wear items in these, also be sure the subframe is nice and tight and in the right place.  The subframe has some adjustability so if it were a little loose it will move around.  

Sounds like the motor mounts are where I need to be looking then!  As far as I recall, I don't think I would have touched any of the subframe fasteners but I'll look there as well.

Don't overlook the swaybar, especially the end links.

Appleseed said:

Don't overlook the swaybar, especially the end links.

Endlinks should make noise when the two ends of the suspension move in opposite directions though, like hitting a bump with one wheel. Also there would be little to no noise on accel/decel.

I had that exact same noise on my 3, in the end it was the front bush in the LCA.. I couldn't replicate it with the car stationary, only when driving..

GameboyRMH said:

Appleseed said:

Don't overlook the swaybar, especially the end links.

Endlinks should make noise when the two ends of the suspension move in opposite directions though, like hitting a bump with one wheel. Also there would be little to no noise on accel/decel.

We had a similar knocking sound on our 5. It was several years ago so I don't remember the exact circumstances when it made the sound but it turned out to be the sway bar bushings. They seemed to be pretty soft and probably could be easily damaged by excessive heat.

Also thinking sway bar.  I lifted an old Cherokee years ago and didn't have it tightened up enough and it popped like it was on a bind sometimes when turning sharp or starting off in reverse. 

Ive seen a bunch of bad trans and motor mounts in the Mazda 5. The clunk when coming to a stop, does it coincide with a downshift?

The sway bar was my first stop since it's almost always the damn swaybar.  But in this case, the bushings and endlinks look good and there was no movement with a prybar.

I've got to get the ticking noise solved on the motorhome first and then I'm going to get the 5 back up on the lift and check out the motor mounts and lca bushings.

Have mazda5, had suspension clunk. Took it to two different shops, had a shop replace the entire right stut/spring combo because that's what they said. Clunk didn't go away. Checked sway bar, wasn't loose at all.  Bought sway bar bushings because I tried everything else and it was cheap. Replaced, and clunk went away. 

I think I found it.

When I was putting it back together, I had this rubber but that I couldn't figure out:

The astute among you will be saying "you dummy, that's part of the transmission mount!"

Turns out, that's part of the transmission mount.  Of course now I have to get myself to the parts store to pick up a replacement, but I think that's gon a take care of it.

Nope.  I didn't found it.  Despite missing a chunk, the transmission mount was apparently not making any noise because the popping / clunking is still there.  I guess I'll just throw new mounts at the other positions next.

wae said:

Nope.  I didn't found it.  Despite missing a chunk, the transmission mount was apparently not making any noise because the popping / clunking is still there.  I guess I'll just throw new mounts at the other positions next.

If this car is the same mechanically as the 10-13 Mazda3 (i think so?) you can upgrade the rear/lower mount to one from a Focus EV which is solid rubber with no voids.  It's obviously stiffer and keeps the whole drivetrain from moving around so much.  You get a little bit more NVH, but for me anyway this was totally acceptable.  Not nearly as loud as things like polyurethane mounts.  You do need to replace one of the bolts as the threads in the mount do not match the stock Mazda bolt.

This is the exact one i bought and installed 5 years ago, link says out of stock but should be available elsewhere?

https://www.amazon.com/gp/product/B00W3SFJO4/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

On a related note back in summer 2020 I spent half the summer replacing front suspension parts chasing down a front end clunk on the same car ('10 mazda 3).  Started out replacing obviously-worn ball joints, but that didn't solve it.  After replacing damn near everything else that felt even slightly worn (tie rod ends, control arms, wheel bearings, sway bar stuff) I replaced the OE inner tie rods even though I could not feel any play in them at all... poof, the problem was gone.

I just realized that I did wind up fixing this.  The transmission side mount didn't seem to clear it up, despite a bit of it having broken off, but back in February I bought a motor mount for the right side and set it in the shop for about 6 months to properly age:

After I felt like it had finally fully ripened, I installed it and the noise has been gone ever since.

Just wanted to wrap that up because "I have this problem" posts on the Internet drive me batty (battier?) when there's no resolution posted.