jmayfield23

So my car has been shaking whenever I brake from about 45 mph and up. From 45 mph and down, it doesn’t shake as much, but still slightly shakes.

Decided to to try some troubleshooting

1. I cleaned the wheel hub with a wire brush and brake cleaner. It was heavily covered by rust and bumps. Cleaned it until smooth and raw metal

2. I cleaned the rotor where it contacts the wheel hub (also covered in rust) and the surface of it with brake cleaner.

3. Cleaned the calipers where brake pads contact the caliper with a wire brush until raw metal is showing.

4. Cleaned the ends of the brake pads, and brushed off brake dust.

Last but not least,

5. Cleaned and greased guide pins


Outcome:

Didnt do a damn thing. Car still shakes at the same speeds. Kind of narrowing down to a warped rotor.

Could getting my rotor resurfaced help maybe?
What else could I check that could be causing this?

It doesn’t shake when driving normally, so wheels are pretty balanced.

Also when coming up to a stop sign, going pretty slow, the car feels like it is pulsating forward and backward as if it is catching on something

MP4.2+6.0

Search on prior threads. Google is your friend.

As a clue--besides the usual rotors early guess--think upper control arms and how they are easily the number one or two D3 suspension issue (along with air struts). A search--and finding my prior posts--should help connect the two. Have you checked them at all? When not if... Certainly by 100K miles w/ out any prior work, or also prior work involving a variety of junk parts out there, and you've got the ingredients.

Report back w/ some reading in hand, plus mileage, year and general geographic location.

jmayfield23

I’ll have to take a look in the morning. Also there is like this squeaking noise that comes out of my front end when I go over big bumps. Always thought it was my sway bar links, but after looking at them today, they almost look brand new.

My car is a 05 with 170,XXX miles, and I’m located around 100 miles east of Indianapolis

MP4.2+6.0

Squeaking noise fits too--if not sway bar links or bar main bushings. At 170K, your upper control arms are past shot if never replaced. If replaced once or even twice by non OE, shot too. Even if replaced by OE (Lemforder) once before, likely still shot.. As in, car should be on about its third round of OE control arm (bushings) by about now The inner bushings at bolt up points are where they usually fail. Most non OE arms or bushings are cheap not just on price but on poor quality/longevity, and the OE ones are already overworked in the set up.

Know that in Midwest your pinch bolt that holds these in will likely be the (really...) hard part of job if my guess proves out. Literally start spraying it with penetrant tomorrow and at various times thereafter if you get parts in a week or so. Absolutely replace that pinch bolt. Search on prior posts for how to's, tips, nightmare scenarios if you start prying on the steering knuckle or start hitting it with hammer, etc.

jmayfield23

How will I know if it’s bad? And also is it a part I should be able to just pull off and put back on without lifting the knuckle to line it up?

jmayfield23

Also do I need to replace the whole bar or just the bushings?

dvs_dave

Upper control arm bushings need replacement. Common wear item, and shaking under braking is a common symptom when they get really bad. The bushings can be replaced within the existing arms.

Jack88

Yep, I think I got OEM brand ones from FCP Euro or some such place and replaced all of my uppers. Also a few of the lowers. Cost me $180 or so to pay someone else to press them in, and that was probably on the high side from what most people should see.

PaulW

Did you measure the rotor runout before and after you cleaned the hubs? If it's not less than 0.002", you'll still have shaking. I had something very similar, I put on new front rotors last year but didn't clean the hubs, and ended up having about 0.030" runout. A few months ago I spent an hour or so each side cleaning everything up and got the runout down to 0.002" or less, it has resolved 95% of the problem.

PaulW

Here is a video of after that compares the before.