Metalic grinding noise

[Kissmyblass]

I've always had this metalic grinding noise coming from under my car. It is relative to the vehicle speed The previous owner said it was the rear brakes,I replaced the pads and rotors , this didn't help. I know the rear dif seal is leaking as was a common problem on these [88 markvii] but i filled that up and no change. The u jouints seem good ,anyone experience this before .......

 

[WALT]

YEESSIREEE
Got a 91 LSC that has almost the exact same noise you are describing--
Have not gotten around to pulling wheels off and checking brakes
but it doesnt appear to be hurting anything --You say
you have replaced the pads and rotors with no change --Thats good -- Keeps me from going there --
It does not make any kind of normal rear end noises ( gear grind / bearings howl )
So I am going to focus on things like backing plates / caliper mounts / park brake
assembly release - etc etc
Still too busy fighting the suspension but will let you know what
I find on the rear end noise issue when I get to it ---
WALT

 

[JoshMcMadMac]

It could be the brakes. The pads need to be set to the proper tolerance, which you must be careful to do. Simply replacing the pads and rotors will not solve the issue; properly adjusting the brakes might.

 

[Kissmyblass]

It could be the brakes. The pads need to be set to the proper tolerance, which you must be careful to do. Simply replacing the pads and rotors will not solve the issue; properly adjusting the brakes might.

Any info or leads on the proper procedure,,,,,,,,,,

 

[MonsterMark]

I've always had this metalic grinding noise coming from under my car. It is relative to the vehicle speed The previous owner said it was the rear brakes,I replaced the pads and rotors , this didn't help. I know the rear dif seal is leaking as was a common problem on these [88 markvii] but i filled that up and no change. The u jouints seem good ,anyone experience this before .......

Once the car has been "SAFELY" lifted in the rear, spin the wheels and listen for brake noise, or gear noise in the differential or bearing noise (I suspect) in the hub. Then go from there. Beats sticking your head under the door to listen sas the car sails 30 mph down the road.

 

[WALT]

If you still need the data, I will get the maintenance manual out and send you the correct procedures for setting up the rear brakes --
Still fighting my suspension and wiring problems
so I havent pulled the wheels on mine yet --

 

[Mad Maxx]

noise under car

my 88 lsc makes a noise like that..... i just replaced all rotors and pads.....it was gone for a while but came back

my check abs light is on....was thinking maybe it was causing pressure on pads.... havnt got into that yet.....

it starts after ive been driving for a while.....sounds like loud crickets....continuous......doesnt vary with speed......doesnt change when i apply brakes.....only stops as i roll to a stop from 3 down to zero miles an hour

ive jacked up the front immediately upon getting into the driveway and spun the wheels....not a peep

ive jacked the back up ....put it in gear......and reved up to 50 on speedo ....up and down.....no noise

i had it in a differential shop and they checked out the gears and bearings and fixed all ..... didnt affect the noise

im hoping when the abs problem is fixed it will dissappear .......almost like fingernails on the blackboard....verrrrry anoying

 

[OldSchool1]

my 88 lsc makes a noise like that..... i just replaced all rotors and pads.....it was gone for a while but came back
...

Has anyone heard this while walking next to the car?
If so, from which side?
Does it also occur in reverse?
If so, from which side?

Outside of our engines, there's like only five external rotating assemblies:
(4) wheels
(1) driveshaft

Rubbing noises mean wear. Wear leaves evidence. I'd eyeball the entire drive shaft. The other four places are easy. I'd start by looking for something protruding in the wheel well. If that doesn't produce anything then lift, support, and inspect each wheel assembly with a fine tooth comb.