Okay, I'm working on my better half's 2000 Monte SS.


It had a heavy shudder under acceleration, which I learned was caused by the CV shafts (thanks to members here!). I replaced the CV shafts, and front brake pads around the 1st of November. The shudder went away, which is great, but a new problem has come up...


There is now a clicking or thunking sound when you are coming to a stop. It sounds exactly like a bad CV axle. The noise developed about a week after changing the CV axles, so I assumed it was a bad axle, but not sure which side. When I'm driving and she's in the passenger seat, she says it's coming from the passenger side, but I feel like it's on the driver's side. If we switch sides, it's the same type of scenario. Each feels like it's coming from our respective side. There is no noise when turning, unless you're braking at the same time. The noise is most prominent when braking in a straight line. Also, it's most noticeable at about 15mph down to just before complete stop (maybe 5mph or so). When braking from 45-50, the noise seems to start about 15-20 mph. It also seems to be in time with the rotation of the tires (the slower you get, the slower the noise gets).


I took a chance and changed both CV shafts today for new units from Advance (their CarQuest line). So this is now the second set of new CV shafts in under a month. The clicking noise is still there.


I have double and triple checked the brake assembly for anything that doesn't look right, and also my torque on the wheels (making sure it wasn't a loose wheel). Nothing looks out of place.


I'm a pretty decent mechanic (at least I think so hahahaha) but I'm not as familiar on this car as I am my older vehicles. Maybe (hopefully) someone can point out something here I missed or overlooked.


Sorry so long for a first post, but I'm trying to be as detailed as possible. Thanks in advance for any help!

 

I read your post a few times , sounds better than most description so your good. My first thought when I hear about shuddering under acceleration is the transmission going south , but hopefully a worn shaft was the problem. As for the noise I would check a few things. CV shaft nut torque 118 ft pounds , were the rotors replace ? I seen the wheel stud holes oversized on a few where it's actually to big. Remove the brake pads and check the caliper bracket ( my guess) and make sure tgem bolts are tight , as I recall there supposed to over 100 ft lbs and confirm the clips are on and .brake pads move freely. Maybe something here will help you . Good luck

 

When I pulled the original CV shaft out, I opened the inside joint from the passenger shaft and found loose rollers (needles) from the bearings inside. My guess is one of the roller pieces inside (not sure of the technical term) chewed up a bearing and that caused the shudder. After replacing the shafts, the shudder was gone, but now I have the "new" noise... Honestly, it might have been there before and we never noticed it, but for about a week, the car was nice and quiet and smooth, and then this noise when stopping...

Rotors were not replaced, but after reading this I pulled the wheels and brakes off to go over everything again. The rotors are true (laid them on a piece of flat glass and felt around them with a feeler gauge... poor man's warpage gauge hahaha). I did notice they there is a little wobble where the center hole and wheel stud holes are a bit oversize compared to the hub/studs. I looked over the edges very closely, but couldn't find any indication that one (or both) may have "walked" to the edge of what the play allowed and caused the issue. No abnormal marks on the calipers, brackets, etc either. I reassembled everything and did a bit more testing (driving), and the noise is still there, but under hard braking it's less noticeable. The harder I brake, the less it seems to be present. Oh, when I replaced the brake pads, I cleaned the calipers pretty thoroughly with brake cleaner and a wire brush, then relubed with caliper slide lube. I checked all my bolts at least twice (most got checked 3 times) for proper tightness. The only bolt i'm not 100% sure on is the CV axle bolt. My torque wrench only reads 110 Ft/lb, but I maxed it out, so I'm close.

Hopefully we can get this figured out... sure would make the better half happy!

 

Chasing a noise down can sure be a pain. One of the few other things I can think of are worn mounts . Perhaps it's causing the engine/transmission to rock enough to cause a noise. Can check by having someone switch between reverse and drive and watching engine rock from the side . Worn bushings are also culprits but are harder to inspect. Definitely don't want to send you on endless chases. Hopefully others have some ideas also. Good luck

 

Reading this, I am just reaching at ideas (my suggestions are NOT because I think that is it, but when against a wall, inspect some odd ball ideas).... But perhaps start looking at some other items, simple to feel out and decide if parts are needed after some inspection.
1. - Check the front wheel hubs. Simply jack up the front of the car. Wiggle the wheel left to right, top bottom and then diagonally. If the hubs are failing, typically the wheel is going to wiggle in all directions you test of play.
2. - Make sure the brake calipers are properly sliding on the guide pins. Also, one pin should have a rubber bushing on it. Make sure you do not over grease the pins, especially the one with the bushing. Over greasing can create a vacuum/suction issue, interfering with the caliper sliding, typically cocking the caliper while braking. This guy here is guilty of that once (took for EVER to find it, luckily my eyes thought they caught a brake pad wear problem I confirmed with measuring calipers, it was tiny but it was there and then I hunted down the issue, found it, fixed it and slapped on new pads).
3. - Make sure the bolts holding the caliper bracket to the spindle/knuckle are tight. Technically per the shop book (and three bad experiences), those bolts require a drop or two of red loctite (that style caliper, regardless of GM/Ford/Mopar is known for those bolts backing out without loctite).
4. - I would be surprised if these are related, but hey, while the car is in the air.... Do a general check on tie rods, ball joints, condition of the control arms and control arm bushings, sway bar end links, sway bar bushings and the sway bar itself (known the crack as a result of being hollow inside)

Best thoughts I have at the moment. Good luck and share what you find!

 

Been a little while, here are some updates and new info...

Problem noise is still present.

Now I am getting messages on the dash to "service traction system" and similar (can't remember them all at the moment). Sometimes from a stop, there will be a message saying "traction system active" or similar, and the car simply won't go for a few seconds.

Today, the better half was driving home from work, called me on the way and said "something doesn't feel right on the right front."

She gets home, I check tire pressure first (that tire has a slow leak at the bead, so my first thought). 40psi, so not the issue. Pull the tire and get to feeling around and wiggling/shaking things, and here is what I found:

Slight play at the outer tie rod ends (was not present when I posted last on this issue, I checked). Maybe 1/16" play each side. Replacement needed, followed by alignment.

When I grabbed the end of the passenger (right) inboard cv knuckle (at the boot), there is a lot of play there. Probably 1/4" vertically. Like the end is pivoting inside the trans, or is there a bearing there at the flange that might have gone bad? If so, is it replaceable without pulling the trans? Is this an issue that needs to be addressed now (take the car off the road immediately), or can she continue to drive it until parts come in? The driver's side also has some vertical play, but a lot less, maybe 1/16" or less. Just enough to feel it more than see it. One note here: When changing the driver's side CV, the center shaft inside the trans came out with the old axle. I had indexed the axle position, and after separating the old CV end from the center axle, I reoriented it and put it back in at the same position it was. Not being too familiar with the inner workings of these transmissions, I called a local trans shop who told me it was no big deal as long as it seated back securely, which it did.

Most of the control arm bushings show general wear, but no play or slop.

Up top, I did notice the engine seems to rock more than I feel it should when stopped and shifting drive to reverse and back. Looks like the upper engine mounts are due for replacement sooner rather than later.

I think I said before that I'm a pretty competent mechanic, but I know there are those out there much more familiar with these cars than I am. My main worry right now is the play at the CV axle end by the trans (I think).

Pointers? Tips? Suggestions?

Thanks in advance!

 

The bushing inside the transmission that holds the axle is replaceable but requires a special tool , it xan be changed on the car if you can find or borrow one from a transmission shop. I personally never have changed one . I wish I could help you further. Perhaps try checking YouTube for installation process.Good luck

 

After some looking on youtube, there is a cover that unbolts that has the bushing in it. You can get this cover off with the trans still in the car thankfully. There's a u-pull yard close by with an SS in it (already got some interior trim and such out of it). Heading there tomorrow to see about yanking the whole cover to get us by until new parts come in.

In the meanwhile, if anyone else has suggestions or things to check, I'm all ears...