Help with clunking noise after installing new hubs/axles/bearings!

So, just a few days ago, I installed a set of Karcepts 36mm hubs onto my DC2 Integra. Along with them, I installed a set of cheap (Trakmotive off of Rock Auto) Acura RSX Type S 36mm axles and new Timken wheel bearings. I documented the whole thing in my build thread, over here: 
https://grassrootsmotorsports.com/forum/build-projects-and-project-cars/the-teg-a-dc2-road-to-all-the-hondas-story/258401/page2/

For clarification, the OEM hubs/axles for the DC2 are 32mm. The 36mm hubs/axles are an upgrade. In order to get them to work, Karcepts recommends a set of RSX Type S axles and their B-series transmission spacer (which I used). 

In order to install the new hubs, you have to replace the wheel bearings. Stuff I removed: 

During the install, I ran into a few issues: 

-Karcepts sends you (x2) 1mm shims with the kit, saying in some rare occasions, the axle will hit the knuckle and seize. On the left side, yep, it seized when trying to tighten the axle nut, so I added the shim and was able to tighten it down without it seizing. 

-On the right/passenger side, I popped the axle in, sure enough, it seized against the knuckle, just like the left side... ok, I'll throw a shim on (they only supply you with 2)... nope, still seized. I'm out of shims. I headed down to Ace Hardware, who luckily, had the exact shims Karcepts sent out. Hooray! 2 shims and it's no longer seized.

-After tightening down the right axle, I was having a problem getting the right axle to turn freely with the wheels off and suspension at full droop ... I couldn't see anything it was getting hung up on, but the angle of the axle looked pretty sharp... I turn the car on while on jack stands, thinking I'll row through a gear to see if anything sticks out... As I start to go into gear, the car (right side) has a massive vibration and loud noise... I instinctively go to press on the brakes out of habit- completely forgetting they're not connected. Sigh. I'm hoping I didn't damage the caliper(s) from touching the brakes with no pads to press down on... 

I then put a jack underneath the right side lower control arm, out of morbid curiosity, to see what would happen if I made the axle level... when the axle became level, all noise and vibration went away completely and the axle spun smoothly with ease... was it the angle? Maybe the additional shim(s) took it too far out of spec? 

Either way, I've since contacted Karcepts, and they mentioned that some axles come with dust shields and recommended I try to pop them off or clearance them rather than running the shims, if at all possible (I will be doing this in the near future- I actually have a completely different axle coming for the right/passenger side). 

When I got done, I noted that while the old/stock 32mm right/passenger side axle essentially sat flush against the transmission... I could not get this new 36mm axle fully seated against the transmission: 

^^^^I wrote Karcepts and was essentially told that was completely normal. They said the RSX-S input is about 5mm longer than the DC2 and didn't seem concerned. 

Since installing everything, I now have a popping/clunking noise when braking (lightly?) at very low speeds. I made a video about it, so you can hear what I'm talking about: 

https://www.youtube.com/watch?v=1XKX9zMmdcI

My notes:

-It only occurs when braking, typically only when pressing the pedal (maybe even borderline releasing a bit?) very lightly, at very low speed (around ~5mph or less). 

-It does not occur when accelerating or turning and I also don't hear anything when braking from higher speeds. 

-I'm using the same brake pads and rotors that were on the car before- I never had an issue before. 

-Admittedly, while installing the new 36mm hubs/axles, while the car was in the air, I turned on the car and ran it through a gear to make sure nothing was binding... when I heard a noise/vibration on the right side, I instinctively pressed the brake pedal, even though the calipers weren't connected, like an idiot. I was able to use a C-clamp to press the caliper back in and the car is braking just fine, but I'm not sure if this might be related. 

-When shaking the front wheels (while off the ground), they feel tight. All ball joints (upper, lower and tie-rod) are less than a year old. I can try to add some grease to a couple of them with zerks fittings on them (a bit squeezed out upon removal), but I'm not convinced that is my problem. All ball joints came loose fairly easily with a ball joint separator tool. I did have to fully remove the knuckles to get the hubs out, so all ball joints were loosened and tightened. 

-I can double check that everything is torqued down properly, but I'm 99% sure I torqued everything to factory spec and figured I would be hearing noise at speed if I didn't. 

Before I start burning through money and man-hours, I figured I would ask the hivemind: after hearing the noise on the video and listening to my story, where would you start? What does it potentially sound like to you? 

Thanks in advance! 

Did you dislodge a pad shim when you applied the brakes not on the rotor?  That will make the pads click and clack and clunk in the caliper when you apply the brakes lightly.

Dislodging a pad shim could be a possibility, but as for the caliper or piston, if you didn't eject a piston then you got away with it.

Also your video is set to private, you should change it to unlisted.

Pete. (l33t FS) said:

Did you dislodge a pad shim when you applied the brakes not on the rotor?  That will make the pads click and clack and clunk in the caliper when you apply the brakes lightly.

Actually, the inside shims were disintegrated completely... I'm assuming from my last track day (they're HP+ pads that I used for an open lapping day). Oddly enough, the outside shims are still there... I guess I didn't consider it would be a problem since they were already disintegrated lol. 

I guess that's a pretty good place to start! 

GameboyRMH said:

Dislodging a pad shim could be a possibility, but as for the caliper or piston, if you didn't eject a piston then you got away with it.

Also your video is set to private, you should change it to unlisted.

Yeah, I was shocked that the piston didn't eject itself and I was able to push it back in with a C-clamp with relative ease! 

I have no idea why Youtube automatically made the video private... I just changed it. Thank you! 

I'm sure it would take multiple pumps for the piston to eject itself, last time I changed front pads on the Toyobaru I forgot to pump the brakes to bring the pads close to the rotors again before moving it. I started backing down the driveway, hit the brakes, got nothing, realized what happened and gave it 3 or 4 pumps before I eventually grabbed the handbrake, and I think it took a couple more pumps to get the pads back into position.

It does sound like it could be a brake pad moving around in the caliper bracket and that would be consistent with it only happening under light braking at low speeds.

roninsoldier83 said:

Pete. (l33t FS) said:

Did you dislodge a pad shim when you applied the brakes not on the rotor?  That will make the pads click and clack and clunk in the caliper when you apply the brakes lightly.

Actually, the inside shims were disintegrated completely... I'm assuming from my last track day (they're HP+ pads that I used for an open lapping day). Oddly enough, the outside shims are still there... I guess I didn't consider it would be a problem since they were already disintegrated lol. 

I guess that's a pretty good place to start! 

For clarity, I am talking about the shims that go between the pad and carrier, not the anti noise shims that go on the backing plate.

I had a similar issue when I replaced the front A arms on our forester. I got it all together and my wife complained of a knocking sound in the floor when she would accelerate but especially when she would brake. It turned out I forgot to torque down the bolt that secures the rear of the A arm to the body of the car and it was banging like that. Other than that the drivability was great.

In reply to Pete. (l33t FS) :

Are you talking about the little spring shims/hardware that keep the pads from moving? I think they're called abutment clips. These: 

That was one of the first things I checked- they're all accounted for. However, during reassembly, the upper one on the left/driver's side did fall off. I put it back in there, but it's seemingly not as tight as it was previously. I ordered a new set, just in case. 

gunner (Forum Supporter) said:

I had a similar issue when I replaced the front A arms on our forester. I got it all together and my wife complained of a knocking sound in the floor when she would accelerate but especially when she would brake. It turned out I forgot to torque down the bolt that secures the rear of the A arm to the body of the car and it was banging like that. Other than that the drivability was great.

I'll re-check torque on everything. I'm pretty sure I torqued everything down with the suspension loaded, but it had been a long day, it won't hurt to double check. All 6 of the ball joins (3 on each side) have cotter pins in them, making me think I torqued them down. The only other thing I loosened was the spring forks, which also appears to be tight. 

I initially tried to use a slide hammer to pull the hub out, hoping I wouldn't have to remove the entire knuckle, but that was unsuccessful, leaving me having to pull the whole knuckle and smash the old hubs out with a large socket and a hammer. I'm just trying to think of alternative issues- I wouldn't think pulling on the slide hammer (attached to the hub) would have damaged or loosened anything else, but maybe I'm mistaken? 

I had some time to do some troubleshooting tonight:

-All caliper springs/shims are accounted for. I can't move the brake pads with my fingers while the caliper is bolted in place. That doesn't necessarily mean much, as I'm sure my fingers don't generate the force of the caliper. 
 

-Turning the steering wheel full lock in either direction doesn't seem to produce any noise at all. 
 

-I didn't check every nut & bolt with a torque wrench, but all seemed hand tight. I checked a few with a different torque wrench and they were pretty close, close enough I don't think it would matter.

-This noise ONLY appears while braking. I haven't heard it while accelerating or turning at speed. It doesn't seem to matter if the wheels are pointed straight or turning. It doesn't seem to matter if there's a grade or flat ground. And I can only hear it at very low speeds.

-Shaking the wheel unloaded, I don't feel any play, up/down or left/right. 
 

-I re-greased the outer tie rod ball joint, it didn't seem to make a difference.

-The lower ball joints look very flat- they could use some grease for sure... I'm not sure if them needing grease would cause this noise? They do have ports for a zerks fitting, but unfortunately, I have to remove the axles to get to them... it looks like most of the grease came out of them when I separated them from the lower control arm, but they otherwise feel stiff/solid and I don't see any tears. I'll grease them up when the new axles get here. 
 

-I took apart and reassembled the brakes last night, nothing appeared to be out of the ordinary. 
 

-The noise seems to be coming from the right/passenger side, but it's hard to tell.

-Because I had to use those shims, the ABS ring isn't perfectly centered below the ABS sensor, more specifically on the right/passenger side where I had to use 2 shims. I don't think the ABS would be that loud would it? 
 

I'm truly stumped on this one. I'll replace the axles with axles that hopefully won't need shims at all and replace all the brake components... but I truly have no idea what is causing this. It's driving me nuts! 

Is it a single noise when you touch the brake, or is it cyclic with wheel rotation, or engine speed, or anything else?

loose lug nut?

AngryCorvair (Forum Supporter) said:

Is it a single noise when you touch the brake, or is it cyclic with wheel rotation, or engine speed, or anything else?

loose lug nut?

Only occurs when I touch the brakes, at low speeds. No noise/vibration otherwise. 
 

I've retorqued the lugs nuts a few times, nada. 

-I bled the 2 front calipers, thinking maybe air got in them somehow when I pressed the brakes with unloaded calipers... nothing changed.

-I greased the caliper pins... nada.

-I removed the dust shields, thinking maybe they were tapping something... no change at all. 
 

It could be the caliper bracket shims- 1 or 2 are just a tad loose, but I'm not betting on it. 
 

I have no idea what in the world this is. It could be the axle, as it's likely too long (shimmed out of spec), I just don't understand why the noise is only during braking... and it almost sounds like it's coming from the middle of the car, but I truly can't tell. 
 

If this is somehow axle related, if anyone is looking to run the Karcepts 36mm hubs on a B-series car, I implore you to seek another solution. Their lack of fitment notes is astounding:

-Nothing in their instructions about the axle sticking out of the transmission by several extra mm- meanwhile I'm banging away at it, trying to fully seat the damn thing.

-Nothing about how the shims they send you should only be used as a last resort and you should try to clearance the axles/remove the shielding before using them.

-Absolutely nothing about if you try to spin the wheels unloaded, the right side vibrates like crazy and feels like it's going to fly off. 
 

Had I known about any of these issues beforehand, I absolutely never would have bothered with these stupid things. They may work just fine on a K swapped car, but on my setup, this is absolute rubbish! Having been a long-time Karcepts fan, I'm disappointed to say the least. 
 

I'm hoping that by banging on the right axle, trying to seat it further into the transmission, I didn't somehow cause this issue... all for some berkeleying extended wheel studs! Lesson learned. 

Does the noise change if trans is in neutral or in gear? 

One thought is to have someone watch the wheel when slowing to see if there is any funny movement (forward and back, etc). Even if nothing is moving, watching and listening from outside the car may help identify which side is the source.

If nothing looks out of place, I'd try backing the axle nuts off and retorque them.  

Maybe check to make sure rotors are sitting flat on the flange and no crud underneath, lugs are fully seated in flange, and check all the engine and trans mounts to be sure one of them isn't allowing enough movement to cause the noise (see question about if it makes noise whether it's in gear or neutral).. 

I just listened to the video. Is it the three thumping sounds? (Obviously not the clicking of the turn signal)

id like to see a side by side pic of the original RH halfshaft vs the new one that has gap to the transaxle. Specifically the spline length and the position of the retaining wire clip relative to the tip of the spline.

And Check the torque on every fastener again, just for good measure.

In reply to No Time :

I haven't noticed if the noise is while in gear or neutral... that's something I can test. Although at the slow speeds, I typically have the clutch pressed in. 
 

I've tried having my wife watch and listen from the outside, but I fear I may need a more mechanically inclined friend. 
 

The axle nuts are staked... if I back them off, I really need to replace them. 
 

Good ideas on things to check! I certainly hope it's not motor mounts, as they're all essentially less than a year old and OEM. Thank you! 

In reply to AngryCorvair (Forum Supporter) :

Yes, it's the 3 thumping sounds in the video. 
 

As soon as I get some time this weekend, I'll be pulling the axles and comparing. I'll post pics. I'm actually pretty tempted to go back to the smaller stock sized 32mm hubs (likely from SKF), re-do the job and throw these 36mm hubs in the garbage (or on Facebook marketplace?). I'm not making nearly enough power to warrant the larger hubs/axles, I just figured I would add them to future proof the car in the event I ever did a K24 swap and I know they're very durable. 

For reference, the stock DC2 RH side axle compressed length is 23.5"... the LH RSX-S axle (that goes on the RH side of a DC2) is 24.57". I don't know much about axle lengths, but an extra inch seems like a lot. 

roninsoldier83 said:

For reference, the stock DC2 RH side axle compressed length is 23.5"... the LH RSX-S axle (that goes on the RH side of a DC2) is 24.57". I don't know much about axle lengths, but an extra inch seems like a lot. 

I agree

if I wanted to look up the axles on Rock auto, what year make model engine trans would I put in for each?

AngryCorvair (Forum Supporter) said:

roninsoldier83 said:

For reference, the stock DC2 RH side axle compressed length is 23.5"... the LH RSX-S axle (that goes on the RH side of a DC2) is 24.57". I don't know much about axle lengths, but an extra inch seems like a lot. 

I agree

if I wanted to look up the axles on Rock auto, what year make model engine trans would I put in for each?

I actually got the lenghts from Rock Auto (Trakmotive axles). I used the following year, make & models: 

-1996 Acura Integra (all trim levels are the same that year, technically all years are the same, with the exception of the Type R). 

-2002 Acura RSX Type S (the Type S does have a different diameter vs the base model RSX). 

^^^All manuals (not sure if the axles are any different for autos anyway?). 

If you are going to take the nuts off the axles this weekend, before removing them, measure the distance from the end of the thread to the nut so you can see if you ran out of thread when torquing them down. 

You should be able to reuse the nuts by swapping sides (passenger side nut on drivers side axle, so the staking is in a different spot). 
 

I pulled the axles today... I have a potential theory: 

1. I should have mentioned something: when I installed them the first time, I only used 1 shim on the left/driver side, whereas I had to use 2 shims on the right/passenger side. When I put the axle nuts on, I torqued them down to spec, but before staking them down, I took the car around the block to see if it drove ok. When I came back, I double checked the torque (220 ft-lbs) before staking the axle nuts... on the left/driver side, the axle nut didn't move in the least... on the right/passenger side, it actually did require a bit of extra torque. The shims should be pressed up against the bearing/axle, but it makes me wonder if having 2 shims causes them to squirm around just a bit, as the shims are not a remotely tight fit on the axle. 

All of the lug studs were tight/fully installed. 

The axle on the left/passenger side stuck out past the nut by about 1mm... on the right/passenger side, the axle nut was roughly flush with the axle (likely due to the extra 1mm shim used). The whole nut appeared to be threaded, so I'm assuming there was enough thread to torque it down? But maybe that was an issue? 

Karcepts was right about some aftermarket axles having metal/rubber dust covers on them. If only they would have included that in their instructions... there's certainly a possibility that removing the dust shield could have negated the need for the shims. At this point, I don't care, I don't want to keep pulling things apart and putting them back together- I'm going back to a 32mm setup (SKF hubs and bearings are on their way). But, for anyone that finds this in the future, remove the dust shields from the axles: 

I sat the axles next to each other... I know Karcepts says they will work... but there's about an inch difference in their total length. 

Left/driver's side (technially the "right" side for an RSX-S): 

Right/passenger side (technically the "left" side for an RSX-S): 

Compared using the Karcepts B-series spacer (right/passenger side): 

Without the Karcepts spacer (holding it in my hand):

I'm sure these will "work", but given the disparity in length (especially noticeable on the right/passenger side), I'm going to pass. I'm wondering if the extra length also contributed to the binding/noise on the right/passenger side at full droop. Either way, I might go back to this setup if I ever K-swap the car, but for a B-series making ~160whp, I'm going back to the stock 32mm setup. Unless you're boosted and making big power, I wouldn't recommend this setup on a B-series car.