Rear end noise
Cadillac
 

Cadillac Forums | Help Us Help You | Advertise | Cadillac Parts | Cadillac News | Cadillac Classifieds / (Old System)

Cadillac Technical Archive | Cadillac Dealers | Cadillac Reviews | Cadillac Dealer Reviews | Cadillac Vendors

CadillacForums.com is the premier Cadillac Forum on the internet. Registered Users do not see the above ads.
+ Reply to Thread
Results 1 to 8 of 8
RWD 19xx-1984 DeVille and Fleetwood,
1985-1996 Fleetwood and Brougham Forum Discussion, Rear end noise in Past Cadillac Vehicle Discussion; I have a noise coming from the rear of my '75 Deville. It is a whine like gear whine. Sounds ...
  1. #1
    bluegrill is offline Cadillac Owners Member
    Automobile(s): 1975 Coupe DeVille
    Join Date
    Oct 2012
    Posts
    40

    Rear end noise

    I have a noise coming from the rear of my '75 Deville. It is a whine like gear whine. Sounds like the sound you get from a manual tranny in reverse. It starts out low in pitch and increases to a high pitch whine with speed. Definitely related only to vehicle speed. Above 55-60 mph it is barely aubile. So, I'm thinking differential. I opened the diff fill plug and stuck my pinky in just to make sure I had lube in there. The color and consistency of the lube in there looks an awful lot like Auto trans fluid. I've only had this car a few months. If someone had put ATF in the differential would it cause a whine like that? Would any damage likely have ocuured? Any opinions would be apreciated.

  2. Remove Advertisements
    CadillacForums.com
    Advertisements
     

  3. #2
    The Ape Man's Avatar
    The Ape Man is offline Cadillac Owners Connoisseur
    Automobile(s): '80 Fleetwood Coupe, 1994 and 1995 Mercedes 140 Coupe
    Join Date
    Feb 2005
    Location
    Southern NJ
    Age
    52
    Posts
    2,096

    Re: Rear end noise

    Some rear axles use ATF. Maybe someone thought it would make the car get 30 MPG. If that's what you have in there change it A.S.A.P.

  4. #3
    cadillac_al is offline Cadillac Owners Connoisseur
    Automobile(s): Cadillac 78 Seville, 78 Coupe de Ville, 92 Sedan de Ville
    Join Date
    Feb 2007
    Location
    Maine
    Age
    53
    Posts
    2,721

    Re: Rear end noise

    ATF would not be good in there. I have never heard of anybody dumb enough to do this so I hope that's not the case. Gear oil is usually very thick and smells bad. This is why I always change fluids when I get a vehicle, just so I know what is in there.

  5. #4
    jayoldschool's Avatar
    jayoldschool is offline GM RWD V8 addict
    Automobile(s): 81 FWB D'Elegance coupe
    Join Date
    Sep 2006
    Location
    Ontario, Canada
    Age
    41
    Posts
    6,800

    Re: Rear end noise

    ATF is nowhere near the viscosity needed for a rear. It should be 80W90 gear oil. Much thicker.

  6. #5
    bluegrill is offline Cadillac Owners Member
    Automobile(s): 1975 Coupe DeVille
    Join Date
    Oct 2012
    Posts
    40

    Re: Rear end noise

    O.K. great. Thanks for the replies. It can't hurt to change it even if I'm wrong. Any idea how much gear oil it takes to fill it up? I think I read some where 4 1/2 pints. Does that sound right?

  7. #6
    SafariOne is offline Cadillac Owners Fanatic
    Automobile(s): 1981Cadillac Fleetwood Brougham D'Elegance Coupe m
    Join Date
    Mar 2008
    Location
    British Columbia
    Posts
    392

    Re: Rear end noise

    If you do have a rear problem it will most likely be the carrier bearing with a noise like that. Try the fluid first and if you still have the noise you can always recoupe the oil.

  8. #7
    deVille33 is offline Cadillac Owners Connoisseur
    Automobile(s): 1977 Coupe (blue), 1977 Coupe (yellow), 1977 Coupe (green)
    Join Date
    Mar 2006
    Location
    Western Massachusetts
    Posts
    1,368

    Re: Rear end noise

    That red fluid could have been an industrial gear lube. In industrial applications where transfer drive units are used, they get their oil from specialty oil producers. They produce a wide selection of lubricants for various applications, from transfer units to bearing lubes, also greases for various applications also. Most of these lubes have a red dye added to identify them. Someone could have substituted one of these gear lubes for rear gear lube and it is most likely the wrong viscosity for the application. Save a dollar, pay more later.

  9. #8
    jayoldschool's Avatar
    jayoldschool is offline GM RWD V8 addict
    Automobile(s): 81 FWB D'Elegance coupe
    Join Date
    Sep 2006
    Location
    Ontario, Canada
    Age
    41
    Posts
    6,800

    Re: Rear end noise

    You fill it until it comes out the fill hole.

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.
If you do not want to register, fill this field only and the name will be used as user name for your post.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Bookmarks

Cadillac Posting Rules

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
Read about Lincoln | Buick | Kia Forte Forum
Need products for your Cadillac? Check out your options at the links below:

custom floor mats | Cadillac Chrome and Black Chrome Wheels | window tinting