Anonimac

OK, so installed Tokico D-Specs, J&M LCAs, and J&M Adjustable Panhard bar this past weekend. Previous upgrades include new rotors and Ultralites. So, everything goes smooth and after install i test drive and i have a metallic grinding/rubbing sound from rear wheels ( i think rear right ) that sounds like the rotor shroud rubbing against rotors. Sound intensifies with speed and is gone when at rest.

Took car in for front upper strut mount TSB and full alignement post all of my suspension upgrades and hoped that after all was properly aligned the rubbing/grinding sound would be gone. No such luck.

So, TSB is done (unrelated, but i'm happy). Car is completely aligned including a new Steeda camber kit, panhard adjustment, whole nine yards, however, i still have this noise. They are trying to tell me that it's probably the aftermarket rotors, but i had those on for at least two months prior to the upgrades i did this past weekend and no noise whatsoever.

So my question is, what can i look at that i could have affected during installation of the Tokico's, LCAs, and Panhard bar. Could be something simple like something stuck to the brake pad eliminating the necessary clearance/gap and thus rubbing against rotor (side note: i don't see any obvious wear that would narrow it down)? Could i have gotten something between axle and rotor that is also eliminating some of the necessary gap? I'm completely stumped but know with certainty that there was no noise whatsoever for months since my rotor upgrade, but now that i've installed all this other stuff the noise is there.

I plan on taking both rear wheels off this weekend and investigating further but wanted to professional opinions first. Has anyone else experienced this? What could it be?

MustangRetribution

I have experienced something similar I think, though my car is bone stock.

I have a intermitent grinding noise coming from the rear of my car, sounds almost like rattling exhaust, dealer replaced all exhaust hangars to no avail. Now when I bring it back they tell me they can not duplicate the problem .

Like mine, does it occasionally at start up, in low rpm range with engine load, occasionally when I shift gears, its not always their and derened irritating

Anonimac

Just to clarify, mine is DEFINITELY related to the rotation of the wheels (and has nothing to do with the faulty exhaust hangers), which is why i said that the sound intensified with speed and get quieter and slower as i slow down and noexistant when i'm at a stop.

05mustangman

this is just my input but you might want to check out the differential.

Glenn

jack the car up just enough so the tire leaves the ground and give it a spin.

Anonimac

Great suggestion, how do i do that? i've never done it before.

Anonimac

Latest theory...in the process of replacing the LCAs i had to disconnect the ebrake cable...when i put it back on i may have placed the clip on wrong or something and so now that one wheel is under enough tension to cause to caliper to rub against the rotor slightly.

Thoughts? Plausible?

(Will know for sure tomorrow morning)

theedge67

You can test that by driving around the block, then quickly checking the heat on both rear rotors. If one is dragging, one rotor will be noticably hotter than the other.

stangster

If you don't have access to a lift, you could use a pair of jackstands. I'm extra cautious, so I would use the stands plus keep the floorjacks under it. (thats assuming you have jackstands and two floorjacks.)

GixxxerSixxxer

I have the same **** problem. I have lowered my car about 2in. and done JBA axlebacks. I get a rattle/grind noise about about 1300-1800 rpm when under a load in any gear. At first I thought it was an exhaust problem... Nope, all tight and in line not touching anything. So the next thing I was thinking was the 2piece drive shaft was getting in a little bind since the car is lowered 2inches, but when I start the car and the rpms come down there is something in the rear section that rattles real quick and goes away. I have noticed that if the car is drivin awhile the noise becomes more frequent. Any help would be nice.

Thanx.

theedge67

If you notice the same noise in neutral at startup, it HAS to be exhaust related. Blown baffle in a muffler maybe??

GixxxerSixxxer

never thought of that. that would suck... would a company take a return on that to swap it out with another you think.

MustangRetribution

I have a similar problem to gix, if it was a blown baffle wouldnt it make noise ALL the time, instead of just under certain conditions?


Well I have my car at the dealer right now fixing a bunch of little things since my warrantys up in 20 days, they claim that the clunk I hear when turning and hitting a bump was a losse exhaust hanger so they retitghtened and re aligned my exhaust, so if that noise from the rear goes away I will be happy.

Little Black Pony

Sometimes I get noise from my rear. But that's only when I pass gas. No need to ask a doctor about it.

Sorry, I couldn't help it, the title was too good a set up.


If your rear brakes are dragging then check the rotors for heat damage. That will be the easiest way to determine. I had my right rear brake caliper seize up and it discolored the rotor along with wearing down the pads. I never noticed it was stuck the whole time. It never made any noise either.

Maybe a wheel bearing is shot, they make horriible noise and usually only at certain wheel RPMs.

DarkFireGT

I say put it on some jack stands and have someone give it some gas while you inspect everything. I'd try with the wheels on first to see if you can replicate the noise. If you can, and can't find the source, then pull the wheels off and try to replicate it again.