wierd as# noise comin from the back of my car...........wtf?

[addisonblck]

so i get into my car in the mornings and reverse out of the parking lot to hear a noise that sound alot like a cinder block draggin on concrete. but it does it in intervals. plus it only does it when the car is cold. after i drive it for 30 mins or so it wont do it again. any suggestioins? r might this have sumthin to do with the hicas system?

thanx brad

[Bronze MFP]

after a decently long drive (say 20min or more, highway cruising would be best) stop and feel the rear wheels on your car. if they're hot, your calipers are dragging the pads against the rotors. my car makes a very strange higher pitched noise because of this. but also only in reverse.if thats the case you need to get your rear calipers rebuilt, or buy some remanufacture or known good calipers.anything more than that is a drivetrain issue (transmission, driveshaft, differential or wheel bearings)

[addisonblck]

hmmmmm.....koo.....hopfuly its just da calipers......but thanx bro

[brandonDavid]

yeah, i've had the same type of noise. only happens in reverse and just every now and again. never cotinual. but i'm pretty sure it's just the rear end.

[Project93sx]

I have a HICAS as well, and I have the same issue. I just changed the brakes and rotors all the way around. I have been driving on them and they are working fine. The scraping sound is still there, mostly in the morning, when I back out of the garage. My bet is on the VLSD that comes stock with the HICAS. If you consider all the parts that might make the noise: brakes, wheel bearings, axles, and the vlsd, and you take away all the ones that are not affect by heat, you are left with the vlsd. Heated silicone is what makes the vlsd work. If the car is not being driven, the silicone fillament inside the differential is not being used, and most likely the cold components are scraping against eachother. You also have to consider that the car is at least 14 years old, with most likely the same differential it came with, so a rebuild or a new vlsd may be the only way to fix the problem. I have my eye on a KAAZ 2-way, because the 300zx and 240sx HICAS vlsd are 1.5 way rear ends. I won't go into detail, but I'll tell you that you are going to get alot less immediate response with a 1.5 way vlsd than a 2-way, however it is not usually recommended for regular road applications, and especially not made for use in the rain. A welded differential is a cheaper and pretty affective alternative. Try a changing the differential fluid and see what happens, it may be as simple as that

-Phil in SD

[addisonblck]

soooo........ that would defin. make sense now.... ichecked my brakes n wheels n nun of them were makin noise. im gonna go with vlsd problems.ill c wat happens when i change da fluid.thanx

[sleepyS14]

definitely the ghost of a dead hooker from your past .

[addisonblck]

i swear i took care of it........but mayb i didnt?